class Solution {
public:
    int findLongestChain(vector<vector<int>>& pairs) {
        sort(pairs.begin(), pairs.end(), [](const vector<int> &a, const vector<int> &b){
            return a[1]<b[1];
        });
        int res = 0;
        int end = INT_MIN;
        for(auto pair: pairs){
            if(pair[0]>end){
                end = pair[1];
                res++;
            }
        }
        return res;
    }
};