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