#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  if ((n - 2) % 3)
    cout << 1 << " " << 1 << " " << n - 2;
  else if ((n - 3) % 3)
    cout << 1 << " " << 2 << " " << n - 3;
  else
    cout << 2 << " " << 2 << " " << n - 4;
}
