#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  if (n == 3)
    cout << "1 1 1\n";
  else {
    if ((n - 2) % 3 != 0) {
      cout << "1 1 " << (n - 2) << endl;
    } else {
      cout << "1 2 " << (n - 3) << endl;
    }
  }
}
