#include <bits/stdc++.h>
using namespace std;
int n;
void del(int a[], int x) {
  for (int i = x; i < n - 1; i++) a[i] = a[i + 1];
  n--;
}
int main() {
  int n, x;
  char c;
  cin >> n;
  if (n % 2 == 0)
    x = 2;
  else
    x = 3;
  for (int i = 0; i < x; i++) {
    cin >> c;
    cout << c;
  }
  for (int i = 0; i < (n - x) / 2; i++) {
    cout << "-";
    cin >> c;
    cout << c;
    cin >> c;
    cout << c;
  }
}
