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