#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  scanf("%d", &n);
  int a = 1;
  int b = 1;
  int c = n - a - b;
  while (c % 3 == 0) {
    b++;
    c--;
  }
  printf("%d %d %d\n", a, b, c);
}
