Alkuluku

#include <iostream>
#include <vector>
#define N 32000
using namespace std;
bool z[N];
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  long n;
  cin >> n;
  vector<long> primes;
  for (int i = 2; i < N; ++i) {
    if (!z[i]) {
      for(int j = i; j < N; j += i) {
	z[j] = 1;
      }
      primes.push_back(i);
    }
  }
  for (long i = n + 1 + n%2; i <= 1000000007; i+=2) {
    bool isprime = 1;
    for (long p : primes) {
      if (p*p > i) break;
      if (i % p == 0) {
	isprime = 0;
	break;
      }
    }
    if (isprime) {
      cout << i;
      break;
    }
  }
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED