#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, i;
  char c[101];
  bool flag = 0;
  while (cin >> n >> c) {
    flag = 0;
    if (n % 2 == 0) {
      for (i = 0; i < n; i += 2) {
        if (flag == 0) {
          flag = 1;
          cout << c[i] << c[i + 1];
        } else
          cout << "-" << c[i] << c[i + 1];
      }
    } else if (n % 3 == 0) {
      for (i = 0; i < n; i += 3) {
        if (flag == 0) {
          flag = 1;
          cout << c[i] << c[i + 1] << c[i + 2];
        } else
          cout << "-" << c[i] << c[i + 1] << c[i + 2];
      }
    } else if (n % 3 == 1) {
      cout << c[0] << c[1];
      for (i = 2; i < n - 2; i += 3) {
        cout << "-" << c[i] << c[i + 1] << c[i + 2];
      }
      cout << "-" << c[i] << c[i + 1];
    } else if (n % 3 == 2) {
      for (i = 0; i < n - 2; i += 3) {
        if (flag == 0) {
          flag = 1;
          cout << c[i] << c[i + 1] << c[i + 2];
        } else
          cout << "-" << c[i] << c[i + 1] << c[i + 2];
      }
      cout << "-" << c[i] << c[i + 1];
    }
    cout << endl;
  }
  return 0;
}
