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