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