struct Solution;
impl Solution {
fn triangle_number(mut nums: Vec<i32>) -> i32 {
let mut res = 0;
let n = nums.len();
nums.sort_unstable();
for i in (2..n).rev() {
let mut l = 0;
let mut r = i - 1;
while l < r {
if nums[l] + nums[r] > nums[i] {
res += r - l;
r -= 1;
} else {
l += 1;
}
}
}
res as i32
}
}
#[test]
fn test() {
let nums = vec![2, 2, 3, 4];
let res = 3;
assert_eq!(Solution::triangle_number(nums), res);
}