#include <iostream> #include <algorithm> #include <vector> #include <deque> #include <string> #include <tuple> #include <functional> #include <numeric> #include <cmath> #include <iomanip> #include <map> #include <random> //#include "toollib.h" #define INT_MAX 2147483647 #define Loop(i, n) for(int i = 0; i < (int)n; i++) #pragma warning (disable:4018) using namespace std; typedef long long int lint; //***** Main Program ***** bool judge_prime_numbers(int n) { if (n == 1) return false; if (n == 2) return true; else if (n % 2 == 0) return false; else { bool judge = true; for (int i = 3; i <= sqrt(n); i = i + 2) { if (n%i == 0) { judge = false; break; } } return judge; } } int main() { int N; cin >> N; for (int i = N - 100; i <= N + 100; i++) { if (i == 1) continue; if (!judge_prime_numbers(i)) { cout << i << endl; break; } } return 0; }