版权声明:假装有个原创声明……虽然少许博文不属于完全原创,但也是自己辛辛苦苦总结的,转载请注明出处,感谢! https://blog.csdn.net/m0_37454852/article/details/88430206
#include <algorithm>
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <ctime>
#include <cstring>
#include <string>
#include <vector>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <deque>
using namespace std;
const int MAX = 100010, INF = 1<<30;
int N, E;
int S[MAX] = {0};
int main()
{
scanf("%d", &N);
for(int i=1; i<=N; i++) scanf("%d", &S[i]);
sort(S+1, S+N+1, greater<int>());//从大到小排序
for(int i=1; i<=N && S[i]>i; E=i, i++);//找到E天大于E的最大的E
printf("%d", E);
return 0;
}