#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, a, b, c;
  cin >> n;
  a = n - 2;
  b = 1;
  c = 1;
  if (a % 3 == 0) {
    a = n - 3;
    b = 2;
    c = 1;
  }
  cout << a << " " << b << " " << c;
  return 0;
}
