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