use std::cmp;
let result = cmp::min_by_key(2, -1, |x: &i32| x.abs());
assert_eq!(result, -1);
let result = cmp::min_by_key(2, -3, |x: &i32| x.abs());
assert_eq!(result, 2);
let result = cmp::min_by_key(1, -1, |x: &i32| x.abs());
assert_eq!(result, 1);