#include <iostream>
#include <vector>
#include <unordered_map>
int main()
{
    int n;
    std::cin >> n;
    std::vector<int> v(n);
    int biggest_number = -2e9, smallest_number = 2e9;
    std::unordered_map<int, int> cnt;
    for(int i = 0; i < n; i++) {
        std::cin >> v[i];
        if(biggest_number < v[i]) {
            biggest_number = v[i];
        }
        if(smallest_number > v[i]) {
            smallest_number = v[i];
        }
        cnt[v[i]]++;
    }
    while(smallest_number <= biggest_number + 1) {
        if(cnt[smallest_number] == 0) {
            std::cout << smallest_number << std::endl;
            break;
        }
        smallest_number++;
    }
    return 0;
}