#include <iostream>
#include <algorithm>
 
using namespace std;
 
int main(void)
{
	int N;
	cin >> N;
 
	int * A = new int [N];
 
	for (int i = 0; i < N; i++)
		cin >> A[i];
 
	sort(A, A + N);
	int answer = 1;
	for (int i = 0; i < N; i++)
	{
		if (answer != A[i]) break;		//다르다면 중지
		for (int j = i + 1; j < N; j++)	//중복된 값 무시
		{
			if (A[i] == A[j]) i = j;
			else break;
		}
		answer++;
	}
	cout << answer;
	delete[] A;
}

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NQo0IDEgMiA3IDgK

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