You are given n pairs of numbers. In every pair, the first number is always smaller than the second number.
Now, we define a pair (c, d) can follow another pair (a, b) if and only if b < c. Chain of pairs can be formed in this fashion.
Given a set of pairs, find the length longest chain which can be formed. You needn‘t use up all the given pairs. You can select pairs in any order.
Example 1:
Input: [[1,2], [2,3], [3,4]] Output: 2 Explanation: The longest chain is [1,2] -> [3,4]
class Solution { public: int findLongestChain(vector<vector<int>>& pairs) { sort(pairs.begin(),pairs.end()); int n = pairs.size(); vector<int>dp(n,1); int maxLen = 1; for(int i=1;i<n;i++) { for(int j=0;j<i;j++) { if(pairs[i][0]>pairs[j][1]) dp[i] = max(dp[i],dp[j]+1); } maxLen = max(maxLen,dp[i]); } return maxLen; } };