# Primitive Type u128

1.26.0 ·## Expand description

The 128-bit unsigned integer type.

## Implementations§

source§### impl u128

### impl u128

1.0.0 · source#### pub fn from_str_radix(src: &str, radix: u32) -> Result<u128, ParseIntError>

#### pub fn from_str_radix(src: &str, radix: u32) -> Result<u128, ParseIntError>

Converts a string slice in a given base to an integer.

The string is expected to be an optional `+`

sign
followed by digits.
Leading and trailing whitespace represent an error.
Digits are a subset of these characters, depending on `radix`

:

`0-9`

`a-z`

`A-Z`

##### Panics

This function panics if `radix`

is not in the range from 2 to 36.

##### Examples

Basic usage:

`assert_eq!(u128::from_str_radix("A", 16), Ok(10));`

Run1.0.0 (const: 1.32.0) · source#### pub const fn count_ones(self) -> u32

#### pub const fn count_ones(self) -> u32

1.0.0 (const: 1.32.0) · source#### pub const fn count_zeros(self) -> u32

#### pub const fn count_zeros(self) -> u32

1.0.0 (const: 1.32.0) · source#### pub const fn leading_zeros(self) -> u32

#### pub const fn leading_zeros(self) -> u32

Returns the number of leading zeros in the binary representation of `self`

.

Depending on what you’re doing with the value, you might also be interested in the
`ilog2`

function which returns a consistent number, even if the type widens.

##### Examples

Basic usage:

```
let n = u128::MAX >> 2;
assert_eq!(n.leading_zeros(), 2);
```

Run1.0.0 (const: 1.32.0) · source#### pub const fn trailing_zeros(self) -> u32

#### pub const fn trailing_zeros(self) -> u32

1.46.0 (const: 1.46.0) · source#### pub const fn leading_ones(self) -> u32

#### pub const fn leading_ones(self) -> u32

1.46.0 (const: 1.46.0) · source#### pub const fn trailing_ones(self) -> u32

#### pub const fn trailing_ones(self) -> u32

1.0.0 (const: 1.32.0) · source#### pub const fn rotate_left(self, n: u32) -> u128

#### pub const fn rotate_left(self, n: u32) -> u128

Shifts the bits to the left by a specified amount, `n`

,
wrapping the truncated bits to the end of the resulting integer.

Please note this isn’t the same operation as the `<<`

shifting operator!

##### Examples

Basic usage:

```
let n = 0x13f40000000000000000000000004f76u128;
let m = 0x4f7613f4;
assert_eq!(n.rotate_left(16), m);
```

Run1.0.0 (const: 1.32.0) · source#### pub const fn rotate_right(self, n: u32) -> u128

#### pub const fn rotate_right(self, n: u32) -> u128

Shifts the bits to the right by a specified amount, `n`

,
wrapping the truncated bits to the beginning of the resulting
integer.

Please note this isn’t the same operation as the `>>`

shifting operator!

##### Examples

Basic usage:

```
let n = 0x4f7613f4u128;
let m = 0x13f40000000000000000000000004f76;
assert_eq!(n.rotate_right(16), m);
```

Run1.0.0 (const: 1.32.0) · source#### pub const fn swap_bytes(self) -> u128

#### pub const fn swap_bytes(self) -> u128

1.37.0 (const: 1.37.0) · source#### pub const fn reverse_bits(self) -> u128

#### pub const fn reverse_bits(self) -> u128

Reverses the order of bits in the integer. The least significant bit becomes the most significant bit, second least-significant bit becomes second most-significant bit, etc.

##### Examples

Basic usage:

```
let n = 0x12345678901234567890123456789012u128;
let m = n.reverse_bits();
assert_eq!(m, 0x48091e6a2c48091e6a2c48091e6a2c48);
assert_eq!(0, 0u128.reverse_bits());
```

Run1.0.0 (const: 1.32.0) · source#### pub const fn from_le(x: u128) -> u128

#### pub const fn from_le(x: u128) -> u128

Converts an integer from little endian to the target’s endianness.

On little endian this is a no-op. On big endian the bytes are swapped.

##### Examples

Basic usage:

```
let n = 0x1Au128;
if cfg!(target_endian = "little") {
assert_eq!(u128::from_le(n), n)
} else {
assert_eq!(u128::from_le(n), n.swap_bytes())
}
```

Run1.0.0 (const: 1.47.0) · source#### pub const fn checked_add(self, rhs: u128) -> Option<u128>

#### pub const fn checked_add(self, rhs: u128) -> Option<u128>

const: unstable · source#### pub unsafe fn unchecked_add(self, rhs: u128) -> u128

🔬This is a nightly-only experimental API. (`unchecked_math`

#85122)

#### pub unsafe fn unchecked_add(self, rhs: u128) -> u128

`unchecked_math`

#85122)Unchecked integer addition. Computes `self + rhs`

, assuming overflow
cannot occur.

##### Safety

This results in undefined behavior when
`self + rhs > u128::MAX`

or `self + rhs < u128::MIN`

,
i.e. when `checked_add`

would return `None`

.

1.66.0 (const: 1.66.0) · source#### pub const fn checked_add_signed(self, rhs: i128) -> Option<u128>

#### pub const fn checked_add_signed(self, rhs: i128) -> Option<u128>

1.0.0 (const: 1.47.0) · source#### pub const fn checked_sub(self, rhs: u128) -> Option<u128>

#### pub const fn checked_sub(self, rhs: u128) -> Option<u128>

const: unstable · source#### pub unsafe fn unchecked_sub(self, rhs: u128) -> u128

🔬This is a nightly-only experimental API. (`unchecked_math`

#85122)

#### pub unsafe fn unchecked_sub(self, rhs: u128) -> u128

`unchecked_math`

#85122)Unchecked integer subtraction. Computes `self - rhs`

, assuming overflow
cannot occur.

##### Safety

This results in undefined behavior when
`self - rhs > u128::MAX`

or `self - rhs < u128::MIN`

,
i.e. when `checked_sub`

would return `None`

.

1.0.0 (const: 1.47.0) · source#### pub const fn checked_mul(self, rhs: u128) -> Option<u128>

#### pub const fn checked_mul(self, rhs: u128) -> Option<u128>

const: unstable · source#### pub unsafe fn unchecked_mul(self, rhs: u128) -> u128

🔬This is a nightly-only experimental API. (`unchecked_math`

#85122)

#### pub unsafe fn unchecked_mul(self, rhs: u128) -> u128

`unchecked_math`

#85122)Unchecked integer multiplication. Computes `self * rhs`

, assuming overflow
cannot occur.

##### Safety

This results in undefined behavior when
`self * rhs > u128::MAX`

or `self * rhs < u128::MIN`

,
i.e. when `checked_mul`

would return `None`

.

1.0.0 (const: 1.52.0) · source#### pub const fn checked_div(self, rhs: u128) -> Option<u128>

#### pub const fn checked_div(self, rhs: u128) -> Option<u128>

1.38.0 (const: 1.52.0) · source#### pub const fn checked_div_euclid(self, rhs: u128) -> Option<u128>

#### pub const fn checked_div_euclid(self, rhs: u128) -> Option<u128>

1.7.0 (const: 1.52.0) · source#### pub const fn checked_rem(self, rhs: u128) -> Option<u128>

#### pub const fn checked_rem(self, rhs: u128) -> Option<u128>

1.38.0 (const: 1.52.0) · source#### pub const fn checked_rem_euclid(self, rhs: u128) -> Option<u128>

#### pub const fn checked_rem_euclid(self, rhs: u128) -> Option<u128>

1.67.0 (const: 1.67.0) · source#### pub const fn ilog(self, base: u128) -> u32

#### pub const fn ilog(self, base: u128) -> u32

Returns the logarithm of the number with respect to an arbitrary base, rounded down.

This method might not be optimized owing to implementation details;
`ilog2`

can produce results more efficiently for base 2, and `ilog10`

can produce results more efficiently for base 10.

##### Panics

This function will panic if `self`

is zero, or if `base`

is less than 2.

##### Examples

`assert_eq!(5u128.ilog(5), 1);`

Run1.67.0 (const: 1.67.0) · source#### pub const fn checked_ilog(self, base: u128) -> Option<u32>

#### pub const fn checked_ilog(self, base: u128) -> Option<u32>

Returns the logarithm of the number with respect to an arbitrary base, rounded down.

Returns `None`

if the number is zero, or if the base is not at least 2.

This method might not be optimized owing to implementation details;
`checked_ilog2`

can produce results more efficiently for base 2, and
`checked_ilog10`

can produce results more efficiently for base 10.

##### Examples

`assert_eq!(5u128.checked_ilog(5), Some(1));`

Run1.67.0 (const: 1.67.0) · source#### pub const fn checked_ilog2(self) -> Option<u32>

#### pub const fn checked_ilog2(self) -> Option<u32>

1.67.0 (const: 1.67.0) · source#### pub const fn checked_ilog10(self) -> Option<u32>

#### pub const fn checked_ilog10(self) -> Option<u32>

1.7.0 (const: 1.47.0) · source#### pub const fn checked_neg(self) -> Option<u128>

#### pub const fn checked_neg(self) -> Option<u128>

1.7.0 (const: 1.47.0) · source#### pub const fn checked_shl(self, rhs: u32) -> Option<u128>

#### pub const fn checked_shl(self, rhs: u32) -> Option<u128>

const: unstable · source#### pub unsafe fn unchecked_shl(self, rhs: u32) -> u128

🔬This is a nightly-only experimental API. (`unchecked_math`

#85122)

#### pub unsafe fn unchecked_shl(self, rhs: u32) -> u128

`unchecked_math`

#85122)Unchecked shift left. Computes `self << rhs`

, assuming that
`rhs`

is less than the number of bits in `self`

.

##### Safety

This results in undefined behavior if `rhs`

is larger than
or equal to the number of bits in `self`

,
i.e. when `checked_shl`

would return `None`

.

1.7.0 (const: 1.47.0) · source#### pub const fn checked_shr(self, rhs: u32) -> Option<u128>

#### pub const fn checked_shr(self, rhs: u32) -> Option<u128>

const: unstable · source#### pub unsafe fn unchecked_shr(self, rhs: u32) -> u128

🔬This is a nightly-only experimental API. (`unchecked_math`

#85122)

#### pub unsafe fn unchecked_shr(self, rhs: u32) -> u128

`unchecked_math`

#85122)Unchecked shift right. Computes `self >> rhs`

, assuming that
`rhs`

is less than the number of bits in `self`

.

##### Safety

This results in undefined behavior if `rhs`

is larger than
or equal to the number of bits in `self`

,
i.e. when `checked_shr`

would return `None`

.

1.34.0 (const: 1.50.0) · source#### pub const fn checked_pow(self, exp: u32) -> Option<u128>

#### pub const fn checked_pow(self, exp: u32) -> Option<u128>

1.0.0 (const: 1.47.0) · source#### pub const fn saturating_add(self, rhs: u128) -> u128

#### pub const fn saturating_add(self, rhs: u128) -> u128

1.66.0 (const: 1.66.0) · source#### pub const fn saturating_add_signed(self, rhs: i128) -> u128

#### pub const fn saturating_add_signed(self, rhs: i128) -> u128

Saturating addition with a signed integer. Computes `self + rhs`

,
saturating at the numeric bounds instead of overflowing.

##### Examples

Basic usage:

```
assert_eq!(1u128.saturating_add_signed(2), 3);
assert_eq!(1u128.saturating_add_signed(-2), 0);
assert_eq!((u128::MAX - 2).saturating_add_signed(4), u128::MAX);
```

Run1.0.0 (const: 1.47.0) · source#### pub const fn saturating_sub(self, rhs: u128) -> u128

#### pub const fn saturating_sub(self, rhs: u128) -> u128

1.7.0 (const: 1.47.0) · source#### pub const fn saturating_mul(self, rhs: u128) -> u128

#### pub const fn saturating_mul(self, rhs: u128) -> u128

1.58.0 (const: 1.58.0) · source#### pub const fn saturating_div(self, rhs: u128) -> u128

#### pub const fn saturating_div(self, rhs: u128) -> u128

1.34.0 (const: 1.50.0) · source#### pub const fn saturating_pow(self, exp: u32) -> u128

#### pub const fn saturating_pow(self, exp: u32) -> u128

1.0.0 (const: 1.32.0) · source#### pub const fn wrapping_add(self, rhs: u128) -> u128

#### pub const fn wrapping_add(self, rhs: u128) -> u128

1.66.0 (const: 1.66.0) · source#### pub const fn wrapping_add_signed(self, rhs: i128) -> u128

#### pub const fn wrapping_add_signed(self, rhs: i128) -> u128

1.0.0 (const: 1.32.0) · source#### pub const fn wrapping_sub(self, rhs: u128) -> u128

#### pub const fn wrapping_sub(self, rhs: u128) -> u128

1.0.0 (const: 1.32.0) · source#### pub const fn wrapping_mul(self, rhs: u128) -> u128

#### pub const fn wrapping_mul(self, rhs: u128) -> u128

Wrapping (modular) multiplication. Computes `self * rhs`

, wrapping around at the boundary of the type.

##### Examples

Basic usage:

Please note that this example is shared between integer types.
Which explains why `u8`

is used here.

```
assert_eq!(10u8.wrapping_mul(12), 120);
assert_eq!(25u8.wrapping_mul(12), 44);
```

Run1.2.0 (const: 1.52.0) · source#### pub const fn wrapping_div(self, rhs: u128) -> u128

#### pub const fn wrapping_div(self, rhs: u128) -> u128

Wrapping (modular) division. Computes `self / rhs`

.
Wrapped division on unsigned types is just normal division.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.

##### Examples

Basic usage:

`assert_eq!(100u128.wrapping_div(10), 10);`

Run1.38.0 (const: 1.52.0) · source#### pub const fn wrapping_div_euclid(self, rhs: u128) -> u128

#### pub const fn wrapping_div_euclid(self, rhs: u128) -> u128

Wrapping Euclidean division. Computes `self.div_euclid(rhs)`

.
Wrapped division on unsigned types is just normal division.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.
Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to `self.wrapping_div(rhs)`

.

##### Examples

Basic usage:

`assert_eq!(100u128.wrapping_div_euclid(10), 10);`

Run1.2.0 (const: 1.52.0) · source#### pub const fn wrapping_rem(self, rhs: u128) -> u128

#### pub const fn wrapping_rem(self, rhs: u128) -> u128

Wrapping (modular) remainder. Computes `self % rhs`

.
Wrapped remainder calculation on unsigned types is
just the regular remainder calculation.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.

##### Examples

Basic usage:

`assert_eq!(100u128.wrapping_rem(10), 0);`

Run1.38.0 (const: 1.52.0) · source#### pub const fn wrapping_rem_euclid(self, rhs: u128) -> u128

#### pub const fn wrapping_rem_euclid(self, rhs: u128) -> u128

Wrapping Euclidean modulo. Computes `self.rem_euclid(rhs)`

.
Wrapped modulo calculation on unsigned types is
just the regular remainder calculation.
There’s no way wrapping could ever happen.
This function exists, so that all operations
are accounted for in the wrapping operations.
Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to `self.wrapping_rem(rhs)`

.

##### Examples

Basic usage:

`assert_eq!(100u128.wrapping_rem_euclid(10), 0);`

Run1.2.0 (const: 1.32.0) · source#### pub const fn wrapping_neg(self) -> u128

#### pub const fn wrapping_neg(self) -> u128

Wrapping (modular) negation. Computes `-self`

,
wrapping around at the boundary of the type.

Since unsigned types do not have negative equivalents
all applications of this function will wrap (except for `-0`

).
For values smaller than the corresponding signed type’s maximum
the result is the same as casting the corresponding signed value.
Any larger values are equivalent to `MAX + 1 - (val - MAX - 1)`

where
`MAX`

is the corresponding signed type’s maximum.

##### Examples

Basic usage:

Please note that this example is shared between integer types.
Which explains why `i8`

is used here.

```
assert_eq!(100i8.wrapping_neg(), -100);
assert_eq!((-128i8).wrapping_neg(), -128);
```

Run1.2.0 (const: 1.32.0) · source#### pub const fn wrapping_shl(self, rhs: u32) -> u128

#### pub const fn wrapping_shl(self, rhs: u32) -> u128

Panic-free bitwise shift-left; yields `self << mask(rhs)`

,
where `mask`

removes any high-order bits of `rhs`

that
would cause the shift to exceed the bitwidth of the type.

Note that this is *not* the same as a rotate-left; the
RHS of a wrapping shift-left is restricted to the range
of the type, rather than the bits shifted out of the LHS
being returned to the other end. The primitive integer
types all implement a `rotate_left`

function,
which may be what you want instead.

##### Examples

Basic usage:

```
assert_eq!(1u128.wrapping_shl(7), 128);
assert_eq!(1u128.wrapping_shl(128), 1);
```

Run1.2.0 (const: 1.32.0) · source#### pub const fn wrapping_shr(self, rhs: u32) -> u128

#### pub const fn wrapping_shr(self, rhs: u32) -> u128

Panic-free bitwise shift-right; yields `self >> mask(rhs)`

,
where `mask`

removes any high-order bits of `rhs`

that
would cause the shift to exceed the bitwidth of the type.

Note that this is *not* the same as a rotate-right; the
RHS of a wrapping shift-right is restricted to the range
of the type, rather than the bits shifted out of the LHS
being returned to the other end. The primitive integer
types all implement a `rotate_right`

function,
which may be what you want instead.

##### Examples

Basic usage:

```
assert_eq!(128u128.wrapping_shr(7), 1);
assert_eq!(128u128.wrapping_shr(128), 128);
```

Run1.34.0 (const: 1.50.0) · source#### pub const fn wrapping_pow(self, exp: u32) -> u128

#### pub const fn wrapping_pow(self, exp: u32) -> u128

1.7.0 (const: 1.32.0) · source#### pub const fn overflowing_add(self, rhs: u128) -> (u128, bool)

#### pub const fn overflowing_add(self, rhs: u128) -> (u128, bool)

Calculates `self`

+ `rhs`

Returns a tuple of the addition along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would have occurred then the wrapped value is returned.

##### Examples

Basic usage

```
assert_eq!(5u128.overflowing_add(2), (7, false));
assert_eq!(u128::MAX.overflowing_add(1), (0, true));
```

Runconst: unstable · source#### pub fn carrying_add(self, rhs: u128, carry: bool) -> (u128, bool)

🔬This is a nightly-only experimental API. (`bigint_helper_methods`

#85532)

#### pub fn carrying_add(self, rhs: u128, carry: bool) -> (u128, bool)

`bigint_helper_methods`

#85532)Calculates `self`

+ `rhs`

+ `carry`

and returns a tuple containing
the sum and the output carry.

Performs “ternary addition” of two integer operands and a carry-in bit, and returns an output integer and a carry-out bit. This allows chaining together multiple additions to create a wider addition, and can be useful for bignum addition.

This can be thought of as a 128-bit “full adder”, in the electronics sense.

If the input carry is false, this method is equivalent to
`overflowing_add`

, and the output carry is
equal to the overflow flag. Note that although carry and overflow
flags are similar for unsigned integers, they are different for
signed integers.

##### Examples

```
#![feature(bigint_helper_methods)]
// 3 MAX (a = 3 × 2^128 + 2^128 - 1)
// + 5 7 (b = 5 × 2^128 + 7)
// ---------
// 9 6 (sum = 9 × 2^128 + 6)
let (a1, a0): (u128, u128) = (3, u128::MAX);
let (b1, b0): (u128, u128) = (5, 7);
let carry0 = false;
let (sum0, carry1) = a0.carrying_add(b0, carry0);
assert_eq!(carry1, true);
let (sum1, carry2) = a1.carrying_add(b1, carry1);
assert_eq!(carry2, false);
assert_eq!((sum1, sum0), (9, 6));
```

Run1.66.0 (const: 1.66.0) · source#### pub const fn overflowing_add_signed(self, rhs: i128) -> (u128, bool)

#### pub const fn overflowing_add_signed(self, rhs: i128) -> (u128, bool)

Calculates `self`

+ `rhs`

with a signed `rhs`

Returns a tuple of the addition along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would have occurred then the wrapped value is returned.

##### Examples

Basic usage:

```
assert_eq!(1u128.overflowing_add_signed(2), (3, false));
assert_eq!(1u128.overflowing_add_signed(-2), (u128::MAX, true));
assert_eq!((u128::MAX - 2).overflowing_add_signed(4), (1, true));
```

Run1.7.0 (const: 1.32.0) · source#### pub const fn overflowing_sub(self, rhs: u128) -> (u128, bool)

#### pub const fn overflowing_sub(self, rhs: u128) -> (u128, bool)

Calculates `self`

- `rhs`

Returns a tuple of the subtraction along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would have occurred then the wrapped value is returned.

##### Examples

Basic usage

```
assert_eq!(5u128.overflowing_sub(2), (3, false));
assert_eq!(0u128.overflowing_sub(1), (u128::MAX, true));
```

Runconst: unstable · source#### pub fn borrowing_sub(self, rhs: u128, borrow: bool) -> (u128, bool)

🔬This is a nightly-only experimental API. (`bigint_helper_methods`

#85532)

#### pub fn borrowing_sub(self, rhs: u128, borrow: bool) -> (u128, bool)

`bigint_helper_methods`

#85532)Calculates `self`

− `rhs`

− `borrow`

and returns a tuple
containing the difference and the output borrow.

Performs “ternary subtraction” by subtracting both an integer
operand and a borrow-in bit from `self`

, and returns an output
integer and a borrow-out bit. This allows chaining together multiple
subtractions to create a wider subtraction, and can be useful for
bignum subtraction.

##### Examples

```
#![feature(bigint_helper_methods)]
// 9 6 (a = 9 × 2^128 + 6)
// - 5 7 (b = 5 × 2^128 + 7)
// ---------
// 3 MAX (diff = 3 × 2^128 + 2^128 - 1)
let (a1, a0): (u128, u128) = (9, 6);
let (b1, b0): (u128, u128) = (5, 7);
let borrow0 = false;
let (diff0, borrow1) = a0.borrowing_sub(b0, borrow0);
assert_eq!(borrow1, true);
let (diff1, borrow2) = a1.borrowing_sub(b1, borrow1);
assert_eq!(borrow2, false);
assert_eq!((diff1, diff0), (3, u128::MAX));
```

Run1.7.0 (const: 1.32.0) · source#### pub const fn overflowing_mul(self, rhs: u128) -> (u128, bool)

#### pub const fn overflowing_mul(self, rhs: u128) -> (u128, bool)

Calculates the multiplication of `self`

and `rhs`

.

Returns a tuple of the multiplication along with a boolean indicating whether an arithmetic overflow would occur. If an overflow would have occurred then the wrapped value is returned.

##### Examples

Basic usage:

Please note that this example is shared between integer types.
Which explains why `u32`

is used here.

```
assert_eq!(5u32.overflowing_mul(2), (10, false));
assert_eq!(1_000_000_000u32.overflowing_mul(10), (1410065408, true));
```

Run1.7.0 (const: 1.52.0) · source#### pub const fn overflowing_div(self, rhs: u128) -> (u128, bool)

#### pub const fn overflowing_div(self, rhs: u128) -> (u128, bool)

Calculates the divisor when `self`

is divided by `rhs`

.

Returns a tuple of the divisor along with a boolean indicating
whether an arithmetic overflow would occur. Note that for unsigned
integers overflow never occurs, so the second value is always
`false`

.

##### Panics

This function will panic if `rhs`

is 0.

##### Examples

Basic usage

`assert_eq!(5u128.overflowing_div(2), (2, false));`

Run1.38.0 (const: 1.52.0) · source#### pub const fn overflowing_div_euclid(self, rhs: u128) -> (u128, bool)

#### pub const fn overflowing_div_euclid(self, rhs: u128) -> (u128, bool)

Calculates the quotient of Euclidean division `self.div_euclid(rhs)`

.

Returns a tuple of the divisor along with a boolean indicating
whether an arithmetic overflow would occur. Note that for unsigned
integers overflow never occurs, so the second value is always
`false`

.
Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to `self.overflowing_div(rhs)`

.

##### Panics

This function will panic if `rhs`

is 0.

##### Examples

Basic usage

`assert_eq!(5u128.overflowing_div_euclid(2), (2, false));`

Run1.7.0 (const: 1.52.0) · source#### pub const fn overflowing_rem(self, rhs: u128) -> (u128, bool)

#### pub const fn overflowing_rem(self, rhs: u128) -> (u128, bool)

Calculates the remainder when `self`

is divided by `rhs`

.

Returns a tuple of the remainder after dividing along with a boolean
indicating whether an arithmetic overflow would occur. Note that for
unsigned integers overflow never occurs, so the second value is
always `false`

.

##### Panics

This function will panic if `rhs`

is 0.

##### Examples

Basic usage

`assert_eq!(5u128.overflowing_rem(2), (1, false));`

Run1.38.0 (const: 1.52.0) · source#### pub const fn overflowing_rem_euclid(self, rhs: u128) -> (u128, bool)

#### pub const fn overflowing_rem_euclid(self, rhs: u128) -> (u128, bool)

Calculates the remainder `self.rem_euclid(rhs)`

as if by Euclidean division.

Returns a tuple of the modulo after dividing along with a boolean
indicating whether an arithmetic overflow would occur. Note that for
unsigned integers overflow never occurs, so the second value is
always `false`

.
Since, for the positive integers, all common
definitions of division are equal, this operation
is exactly equal to `self.overflowing_rem(rhs)`

.

##### Panics

This function will panic if `rhs`

is 0.

##### Examples

Basic usage

`assert_eq!(5u128.overflowing_rem_euclid(2), (1, false));`

Run1.7.0 (const: 1.32.0) · source#### pub const fn overflowing_neg(self) -> (u128, bool)

#### pub const fn overflowing_neg(self) -> (u128, bool)

Negates self in an overflowing fashion.

Returns `!self + 1`

using wrapping operations to return the value
that represents the negation of this unsigned value. Note that for
positive unsigned values overflow always occurs, but negating 0 does
not overflow.

##### Examples

Basic usage

```
assert_eq!(0u128.overflowing_neg(), (0, false));
assert_eq!(2u128.overflowing_neg(), (-2i32 as u128, true));
```

Run1.7.0 (const: 1.32.0) · source#### pub const fn overflowing_shl(self, rhs: u32) -> (u128, bool)

#### pub const fn overflowing_shl(self, rhs: u32) -> (u128, bool)

Shifts self left by `rhs`

bits.

Returns a tuple of the shifted version of self along with a boolean indicating whether the shift value was larger than or equal to the number of bits. If the shift value is too large, then value is masked (N-1) where N is the number of bits, and this value is then used to perform the shift.

##### Examples

Basic usage

```
assert_eq!(0x1u128.overflowing_shl(4), (0x10, false));
assert_eq!(0x1u128.overflowing_shl(132), (0x10, true));
```

Run1.7.0 (const: 1.32.0) · source#### pub const fn overflowing_shr(self, rhs: u32) -> (u128, bool)

#### pub const fn overflowing_shr(self, rhs: u32) -> (u128, bool)

Shifts self right by `rhs`

bits.

Returns a tuple of the shifted version of self along with a boolean indicating whether the shift value was larger than or equal to the number of bits. If the shift value is too large, then value is masked (N-1) where N is the number of bits, and this value is then used to perform the shift.

##### Examples

Basic usage

```
assert_eq!(0x10u128.overflowing_shr(4), (0x1, false));
assert_eq!(0x10u128.overflowing_shr(132), (0x1, true));
```

Run1.34.0 (const: 1.50.0) · source#### pub const fn overflowing_pow(self, exp: u32) -> (u128, bool)

#### pub const fn overflowing_pow(self, exp: u32) -> (u128, bool)

1.38.0 (const: 1.52.0) · source#### pub const fn div_euclid(self, rhs: u128) -> u128

#### pub const fn div_euclid(self, rhs: u128) -> u128

1.38.0 (const: 1.52.0) · source#### pub const fn rem_euclid(self, rhs: u128) -> u128

#### pub const fn rem_euclid(self, rhs: u128) -> u128

Calculates the least remainder of `self (mod rhs)`

.

Since, for the positive integers, all common
definitions of division are equal, this
is exactly equal to `self % rhs`

.

##### Panics

This function will panic if `rhs`

is 0.

##### Examples

Basic usage:

`assert_eq!(7u128.rem_euclid(4), 3); // or any other integer type`

Runsource#### pub const fn div_floor(self, rhs: u128) -> u128

🔬This is a nightly-only experimental API. (`int_roundings`

#88581)

#### pub const fn div_floor(self, rhs: u128) -> u128

`int_roundings`

#88581)source#### pub const fn div_ceil(self, rhs: u128) -> u128

🔬This is a nightly-only experimental API. (`int_roundings`

#88581)

#### pub const fn div_ceil(self, rhs: u128) -> u128

`int_roundings`

#88581)Calculates the quotient of `self`

and `rhs`

, rounding the result towards positive infinity.

##### Panics

This function will panic if `rhs`

is zero.

###### Overflow behavior

On overflow, this function will panic if overflow checks are enabled (default in debug mode) and wrap if overflow checks are disabled (default in release mode).

##### Examples

Basic usage:

```
#![feature(int_roundings)]
assert_eq!(7_u128.div_ceil(4), 2);
```

Runsource#### pub const fn next_multiple_of(self, rhs: u128) -> u128

🔬This is a nightly-only experimental API. (`int_roundings`

#88581)

#### pub const fn next_multiple_of(self, rhs: u128) -> u128

`int_roundings`

#88581)Calculates the smallest value greater than or equal to `self`

that
is a multiple of `rhs`

.

##### Panics

This function will panic if `rhs`

is zero.

###### Overflow behavior

On overflow, this function will panic if overflow checks are enabled (default in debug mode) and wrap if overflow checks are disabled (default in release mode).

##### Examples

Basic usage:

```
#![feature(int_roundings)]
assert_eq!(16_u128.next_multiple_of(8), 16);
assert_eq!(23_u128.next_multiple_of(8), 24);
```

Runsource#### pub const fn checked_next_multiple_of(self, rhs: u128) -> Option<u128>

🔬This is a nightly-only experimental API. (`int_roundings`

#88581)

#### pub const fn checked_next_multiple_of(self, rhs: u128) -> Option<u128>

`int_roundings`

#88581)Calculates the smallest value greater than or equal to `self`

that
is a multiple of `rhs`

. Returns `None`

if `rhs`

is zero or the
operation would result in overflow.

##### Examples

Basic usage:

```
#![feature(int_roundings)]
assert_eq!(16_u128.checked_next_multiple_of(8), Some(16));
assert_eq!(23_u128.checked_next_multiple_of(8), Some(24));
assert_eq!(1_u128.checked_next_multiple_of(0), None);
assert_eq!(u128::MAX.checked_next_multiple_of(2), None);
```

Run1.0.0 (const: 1.32.0) · source#### pub const fn is_power_of_two(self) -> bool

#### pub const fn is_power_of_two(self) -> bool

1.0.0 (const: 1.50.0) · source#### pub const fn next_power_of_two(self) -> u128

#### pub const fn next_power_of_two(self) -> u128

Returns the smallest power of two greater than or equal to `self`

.

When return value overflows (i.e., `self > (1 << (N-1))`

for type
`uN`

), it panics in debug mode and the return value is wrapped to 0 in
release mode (the only situation in which method can return 0).

##### Examples

Basic usage:

```
assert_eq!(2u128.next_power_of_two(), 2);
assert_eq!(3u128.next_power_of_two(), 4);
```

Run1.0.0 (const: 1.50.0) · source#### pub const fn checked_next_power_of_two(self) -> Option<u128>

#### pub const fn checked_next_power_of_two(self) -> Option<u128>

Returns the smallest power of two greater than or equal to `n`

. If
the next power of two is greater than the type’s maximum value,
`None`

is returned, otherwise the power of two is wrapped in `Some`

.

##### Examples

Basic usage:

```
assert_eq!(2u128.checked_next_power_of_two(), Some(2));
assert_eq!(3u128.checked_next_power_of_two(), Some(4));
assert_eq!(u128::MAX.checked_next_power_of_two(), None);
```

Runconst: unstable · source#### pub fn wrapping_next_power_of_two(self) -> u128

🔬This is a nightly-only experimental API. (`wrapping_next_power_of_two`

#32463)

#### pub fn wrapping_next_power_of_two(self) -> u128

`wrapping_next_power_of_two`

#32463)Returns the smallest power of two greater than or equal to `n`

. If
the next power of two is greater than the type’s maximum value,
the return value is wrapped to `0`

.

##### Examples

Basic usage:

```
#![feature(wrapping_next_power_of_two)]
assert_eq!(2u128.wrapping_next_power_of_two(), 2);
assert_eq!(3u128.wrapping_next_power_of_two(), 4);
assert_eq!(u128::MAX.wrapping_next_power_of_two(), 0);
```

Run1.32.0 (const: 1.44.0) · source#### pub const fn to_be_bytes(self) -> [u8; 16]

#### pub const fn to_be_bytes(self) -> [u8; 16]

1.32.0 (const: 1.44.0) · source#### pub const fn to_le_bytes(self) -> [u8; 16]

#### pub const fn to_le_bytes(self) -> [u8; 16]

1.32.0 (const: 1.44.0) · source#### pub const fn to_ne_bytes(self) -> [u8; 16]

#### pub const fn to_ne_bytes(self) -> [u8; 16]

Return the memory representation of this integer as a byte array in native byte order.

As the target platform’s native endianness is used, portable code
should use `to_be_bytes`

or `to_le_bytes`

, as appropriate,
instead.

##### Examples

```
let bytes = 0x12345678901234567890123456789012u128.to_ne_bytes();
assert_eq!(
bytes,
if cfg!(target_endian = "big") {
[0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12]
} else {
[0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]
}
);
```

Run1.32.0 (const: 1.44.0) · source#### pub const fn from_be_bytes(bytes: [u8; 16]) -> u128

#### pub const fn from_be_bytes(bytes: [u8; 16]) -> u128

Create a native endian integer value from its representation as a byte array in big endian.

##### Examples

```
let value = u128::from_be_bytes([0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12]);
assert_eq!(value, 0x12345678901234567890123456789012);
```

RunWhen starting from a slice rather than an array, fallible conversion APIs can be used:

```
fn read_be_u128(input: &mut &[u8]) -> u128 {
let (int_bytes, rest) = input.split_at(std::mem::size_of::<u128>());
*input = rest;
u128::from_be_bytes(int_bytes.try_into().unwrap())
}
```

Run1.32.0 (const: 1.44.0) · source#### pub const fn from_le_bytes(bytes: [u8; 16]) -> u128

#### pub const fn from_le_bytes(bytes: [u8; 16]) -> u128

Create a native endian integer value from its representation as a byte array in little endian.

##### Examples

```
let value = u128::from_le_bytes([0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]);
assert_eq!(value, 0x12345678901234567890123456789012);
```

RunWhen starting from a slice rather than an array, fallible conversion APIs can be used:

```
fn read_le_u128(input: &mut &[u8]) -> u128 {
let (int_bytes, rest) = input.split_at(std::mem::size_of::<u128>());
*input = rest;
u128::from_le_bytes(int_bytes.try_into().unwrap())
}
```

Run1.32.0 (const: 1.44.0) · source#### pub const fn from_ne_bytes(bytes: [u8; 16]) -> u128

#### pub const fn from_ne_bytes(bytes: [u8; 16]) -> u128

Create a native endian integer value from its memory representation as a byte array in native endianness.

As the target platform’s native endianness is used, portable code
likely wants to use `from_be_bytes`

or `from_le_bytes`

, as
appropriate instead.

##### Examples

```
let value = u128::from_ne_bytes(if cfg!(target_endian = "big") {
[0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12, 0x34, 0x56, 0x78, 0x90, 0x12]
} else {
[0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]
});
assert_eq!(value, 0x12345678901234567890123456789012);
```

RunWhen starting from a slice rather than an array, fallible conversion APIs can be used:

```
fn read_ne_u128(input: &mut &[u8]) -> u128 {
let (int_bytes, rest) = input.split_at(std::mem::size_of::<u128>());
*input = rest;
u128::from_ne_bytes(int_bytes.try_into().unwrap())
}
```

Run## Trait Implementations§

1.22.0 · source§### impl AddAssign<&u128> for Saturating<u128>

### impl AddAssign<&u128> for Saturating<u128>

source§#### fn add_assign(&mut self, other: &u128)

#### fn add_assign(&mut self, other: &u128)

`+=`

operation. Read moresource§### impl AddAssign<u128> for Saturating<u128>

### impl AddAssign<u128> for Saturating<u128>

source§#### fn add_assign(&mut self, other: u128)

#### fn add_assign(&mut self, other: u128)

`+=`

operation. Read more1.22.0 · source§### impl BitAndAssign<&u128> for Saturating<u128>

### impl BitAndAssign<&u128> for Saturating<u128>

source§#### fn bitand_assign(&mut self, other: &u128)

#### fn bitand_assign(&mut self, other: &u128)

`&=`

operation. Read moresource§### impl BitAndAssign<u128> for Saturating<u128>

### impl BitAndAssign<u128> for Saturating<u128>

source§#### fn bitand_assign(&mut self, other: u128)

#### fn bitand_assign(&mut self, other: u128)

`&=`

operation. Read more1.45.0 (const: unstable) · source§### impl BitOr<NonZeroU128> for u128

### impl BitOr<NonZeroU128> for u128

§#### type Output = NonZeroU128

#### type Output = NonZeroU128

`|`

operator.const: unstable · source§#### fn bitor(self, rhs: NonZeroU128) -> <u128 as BitOr<NonZeroU128>>::Output

#### fn bitor(self, rhs: NonZeroU128) -> <u128 as BitOr<NonZeroU128>>::Output

`|`

operation. Read more1.22.0 · source§### impl BitOrAssign<&u128> for Saturating<u128>

### impl BitOrAssign<&u128> for Saturating<u128>

source§#### fn bitor_assign(&mut self, other: &u128)

#### fn bitor_assign(&mut self, other: &u128)

`|=`

operation. Read more1.45.0 (const: unstable) · source§### impl BitOrAssign<u128> for NonZeroU128

### impl BitOrAssign<u128> for NonZeroU128

source§### impl BitOrAssign<u128> for Saturating<u128>

### impl BitOrAssign<u128> for Saturating<u128>

source§#### fn bitor_assign(&mut self, other: u128)

#### fn bitor_assign(&mut self, other: u128)

`|=`

operation. Read more1.22.0 · source§### impl BitXorAssign<&u128> for Saturating<u128>

### impl BitXorAssign<&u128> for Saturating<u128>

source§#### fn bitxor_assign(&mut self, other: &u128)

#### fn bitxor_assign(&mut self, other: &u128)

`^=`

operation. Read moresource§### impl BitXorAssign<u128> for Saturating<u128>

### impl BitXorAssign<u128> for Saturating<u128>

source§#### fn bitxor_assign(&mut self, other: u128)

#### fn bitxor_assign(&mut self, other: u128)

`^=`

operation. Read more1.0.0 (const: unstable) · source§### impl Div<u128> for u128

### impl Div<u128> for u128

This operation rounds towards zero, truncating any fractional part of the exact result.

#### Panics

This operation will panic if `other == 0`

.

1.22.0 · source§### impl DivAssign<&u128> for Saturating<u128>

### impl DivAssign<&u128> for Saturating<u128>

source§#### fn div_assign(&mut self, other: &u128)

#### fn div_assign(&mut self, other: &u128)

`/=`

operation. Read moresource§### impl DivAssign<u128> for Saturating<u128>

### impl DivAssign<u128> for Saturating<u128>

source§#### fn div_assign(&mut self, other: u128)

#### fn div_assign(&mut self, other: u128)

`/=`

operation. Read more1.22.0 · source§### impl MulAssign<&u128> for Saturating<u128>

### impl MulAssign<&u128> for Saturating<u128>

source§#### fn mul_assign(&mut self, other: &u128)

#### fn mul_assign(&mut self, other: &u128)

`*=`

operation. Read moresource§### impl MulAssign<u128> for Saturating<u128>

### impl MulAssign<u128> for Saturating<u128>

source§#### fn mul_assign(&mut self, other: u128)

#### fn mul_assign(&mut self, other: u128)

`*=`

operation. Read more1.0.0 (const: unstable) · source§### impl Ord for u128

### impl Ord for u128

1.21.0 · source§#### fn max(self, other: Self) -> Selfwhere

Self: Sized,

#### fn max(self, other: Self) -> Selfwhere

Self: Sized,

1.0.0 (const: unstable) · source§### impl PartialEq<u128> for u128

### impl PartialEq<u128> for u128

1.0.0 (const: unstable) · source§### impl PartialOrd<u128> for u128

### impl PartialOrd<u128> for u128

const: unstable · source§#### fn le(&self, other: &u128) -> bool

#### fn le(&self, other: &u128) -> bool

`self`

and `other`

) and is used by the `<=`

operator. Read more1.0.0 (const: unstable) · source§### impl Rem<u128> for u128

### impl Rem<u128> for u128

This operation satisfies `n % d == n - (n / d) * d`

. The
result has the same sign as the left operand.

#### Panics

This operation will panic if `other == 0`

.

1.22.0 · source§### impl RemAssign<&u128> for Saturating<u128>

### impl RemAssign<&u128> for Saturating<u128>

source§#### fn rem_assign(&mut self, other: &u128)

#### fn rem_assign(&mut self, other: &u128)

`%=`

operation. Read moresource§### impl RemAssign<u128> for Saturating<u128>

### impl RemAssign<u128> for Saturating<u128>

source§#### fn rem_assign(&mut self, other: u128)

#### fn rem_assign(&mut self, other: u128)

`%=`

operation. Read moresource§### impl Step for u128

### impl Step for u128

source§#### unsafe fn forward_unchecked(start: u128, n: usize) -> u128

#### unsafe fn forward_unchecked(start: u128, n: usize) -> u128

`step_trait`

#42168)source§#### unsafe fn backward_unchecked(start: u128, n: usize) -> u128

#### unsafe fn backward_unchecked(start: u128, n: usize) -> u128

`step_trait`

#42168)source§#### fn forward(start: u128, n: usize) -> u128

#### fn forward(start: u128, n: usize) -> u128

`step_trait`

#42168)source§#### fn backward(start: u128, n: usize) -> u128

#### fn backward(start: u128, n: usize) -> u128

`step_trait`

#42168)source§#### fn steps_between(start: &u128, end: &u128) -> Option<usize>

#### fn steps_between(start: &u128, end: &u128) -> Option<usize>

`step_trait`

#42168)