#include <bits/stdc++.h>
using namespace std;
const int INF = 0x3f3f3f;
int main() {
  long long n, a = 1, b = 1, c;
  cin >> n;
  for (long long i = 1; i <= n; i++) {
    if (i % 3 != 0) {
      a = i;
      b = i;
      c = n - a - b;
      if (c % 3 != 0) {
        break;
      } else
        continue;
    }
  }
  cout << a << " " << b << " " << c << endl;
  return 0;
}
