text: #include <stdio.h>
  
  using namespace std;
  
  int main() {
  	int n;
  	scanf("%d", &n);
  
  	int a[3001];
  	for(int i = 0; i < n; ++i)
  		scanf("%d", a + i);
  	sort(a, a + n);
  
  	int res = -1;
  	for(int i = 1; i < n; ++i)
  		if(a[i] != a[i - 1] + 1) {
  			res = a[i - 1] + 1;
  			break;
  		}
  
  	if(a[0] > 1)
  		res = 1;
  
  	if(res == -1)
  		res = a[n - 1] + 1;
  
  	printf("%d\n", res);
  
  	return 0;
  }
  
  