#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base ::sync_with_stdio(0);
  long long int n;
  cin >> n;
  cout << 1 << " ";
  n--;
  for (int i = 1; i <= 2; i++) {
    if ((n - i) % 3 != 0) {
      cout << i << " " << n - i;
      break;
    }
  }
}
