题目：https://pintia.cn/problem-sets/994805260223102976/problems/994805269312159744

这题就是理清逻辑就完事了，比较简单

代码

  1. #include<cstdio>
  2. #include<vector>
  3. #include<algorithm>
  4. using namespace std;
  6. int main(){
  7.     int n;
  8.     scanf("%d", &n);
  9.     vector<int> record(n);
  10.     for(int i = 0; i< n; i++){
  11.         scanf("%d", &record[i]);
  12.     }
  13.     sort(record.begin(), record.end());
  14.     int i;
  15.     for(i = 0; i < n; i++){
  16.         if(record[i] > n - i)
  17.             break;
  18.     }
  19.     printf("%d", n - i);
  20. }