#include <bits/stdc++.h>
int main() {
  int n;
  scanf("%d", &n);
  int a, b, c;
  if (n % 3 == 0) {
    a = 1;
    b = 1;
    c = n - a - b;
  } else {
    a = 1;
    b = 2;
    c = n - a - b;
  }
  printf("%d %d %d", a, b, c);
  return 0;
}
