#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  vector<int> dp(100000001, false);
  dp[0] = true;
  dp[1] = true;
  for (int i = 3; i < 100000001; i += 2) {
    if (dp[i] = false) {
      for (int j = i + i; j <= 100000001; j += i) {
        dp[j] = true;
      }
    }
  }
  cin >> n;
  return 0;
}
