Solution.rs

impl Solution {
    pub fn length_of_lis(nums: Vec<i32>) -> i32 {
        let n = nums.len();
        let mut f = vec![1; n];
        for i in 1..n {
            for j in 0..i {
                if nums[j] < nums[i] {
                    f[i] = f[i].max(f[j] + 1);
                }
            }
        }
        *f.iter().max().unwrap()
    }
}