struct Solution;
impl Solution {
fn min_increment_for_unique(mut a: Vec<i32>) -> i32 {
let mut res = 0;
a.sort_unstable();
let mut prev: Option<i32> = None;
for x in a {
if let Some(y) = prev {
if x <= y {
res += y + 1 - x;
prev = Some(y + 1);
} else {
prev = Some(x);
}
} else {
prev = Some(x);
}
}
res
}
}
#[test]
fn test() {
let a = vec![1, 2, 2];
let res = 1;
assert_eq!(Solution::min_increment_for_unique(a), res);
let a = vec![3, 2, 1, 2, 1, 7];
let res = 6;
assert_eq!(Solution::min_increment_for_unique(a), res);
}