import java.util.*;

class Solution {

    public int solution(int[] citations) {
        int answer = 0;
        Arrays.sort(citations);
        System.out.println(Arrays.toString(citations));

        for(int i= 0;i<citations.length;i++){
            int remainLen = citations.length - i;
            System.out.println(citations[i]+"ll"+ remainLen);

            if(citations[i] >= remainLen){
                answer = remainLen;
                break;
            }

        }
        return answer;
    }

}