#include <bits/stdc++.h>
using namespace std;
const int N = 1e5 + 5;
int arr[N];
int main() {
  int n;
  scanf("%d", &n);
  ;
  if (n % 3 == 0 || n % 3 == 1) {
    cout << "1 1 " << n - 2;
  } else {
    cout << "1 2 " << n - 3;
  }
  return 0;
}
long long power(long long a, long long b) {
  long long r = 1;
  while (b) {
    if (b & 01) r = (r * a) % 1000000007;
    a = (a * a) % 1000000007;
    b >>= 1;
  }
  return r;
}
int gcd(int a, int b) {
  int c;
  while (a != 0) {
    c = a;
    a = b % a;
    b = c;
  }
  return b;
}
