#define _FORTIFY_SOURCE 0
#pragma GCC optimize("Ofast")
#pragma GCC optimize("no-stack-protector")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,popcnt,abm,mmx,tune=native")
#pragma GCC optimize("fast-math")

#include <iostream>
#include <math.h>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <set>
#include <map>
#include <deque>
#include <stack>
#include <unordered_map>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;

const ll N = 1 * 1e7 + 100;
const ll M = 1e4 + 100;
const ll INF = 1e18 + 100;

#define x first
#define y second
#define pb push_back

int firstMissingPositive(vector<int>& nums) {
    int32_t ans = 1;
    int32_t k = INT32_MAX;
    int32_t s = -1;

    for (const int32_t num : nums) {
        if (num > 0) {
            if (num == ans) {
                ans++;
            } else if (num > ans) {
                if (num - ans < k) {
                    k = min(k, num - ans);
                    s = num;
                }
            }
        }
    }

    cout << "s = " << s << endl;
    cout << "k = " << k << endl;
    cout << "ans = '" << ans << endl;

    return s == ans ? s + 1 : ans;
}

int main() {
    int n;

    cin >> n;
    vector<int> a(n);

    for (int i = 0; i < n; i++) {
        cin >> a[i];
    }

    cout << firstMissingPositive(a);
    return 0;
}