#Leetcode# 300. Longest Increasing Subsequence

https://leetcode.com/problems/longest-increasing-subsequence/

 

Given an unsorted array of integers, find the length of longest increasing subsequence.

Example:

Input: [10,9,2,5,3,7,101,18]
Output: 4 
Explanation: The longest increasing subsequence is [2,3,7,101], therefore the length is 4. 

Note:

• There may be more than one LIS combination, it is only necessary for you to return the length.
• Your algorithm should run in O(n2) complexity.

Follow up: Could you improve it to O(n log n) time complexity?

代码：

class Solution {
public:
    int lengthOfLIS(vector<int>& nums) {
        int n = nums.size();
        if(n == 0) return 0;
        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);
            }
        }
        sort(dp.begin(), dp.end());
        return dp[n - 1];
    }
};

　　dp