Description

Submission

O(n^2)

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

        vector<int> dp(n, 1);

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

        return *max_element(dp.begin(), dp.end());
    }
};

O(nlogn)

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

        for(int i = 0; i < n; ++i) {
            auto iter = lower_bound(q.begin(), q.end(), nums[i]);

            if(iter == q.end()) {
                q.push_back(nums[i]);
            } else {
                *iter = nums[i];
            }
        }
        return q.size();
    }
};