class Solution {
public:
    int lengthOfLIS(vector<int>& nums) {
        int n = nums.size();
        if(n == 1) return 1;

        int result = 0;
        // dp[i]: max length end at i
        vector<int> dp(n, 1);

        for(int i = 0; i < nums.size(); i++) {
            for(int j = 0; j < i; j++) {
                if(nums[i] > nums[j]) {
                    dp[i] = max(dp[i], dp[j] + 1);
                }
            }
            result = max(result, dp[i]);
        }

        return result;
    }
};