bool cmp(int i, int j){
    return i>j;
}

class Solution {
public:
    int hIndex(vector<int>& citations) {
        sort(citations.begin(),citations.end(),cmp);
        int i;
        for(i=0;i<citations.size();i++){
            if(citations[i]<(i+1))
                return i;
        }
        return i;
    }
};