#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vec;
typedef vector<string> vecstr;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define NO printf("NO")
#define YES printf("YES")

int main() {
    int N;
    cin >> N;
    rep(i, 201) {
        int num = N - 100 + i;
        if((num > 2 || num < -2) && num % 2 == 0) {
            cout << num << endl;
            break;
        }
    }
}