#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b;
  cin >> a >> b;
  string s;
  cin >> s;
  int c = s.find('-');
  if (c <= 0 || c >= 5) {
    cout << "No" << endl;
    return 0;
  }
  if (s.find('-', c + 1) != -1) {
    cout << "No" << endl;
    return 0;
  }
  if (s.size() - c >= 6) {
    cout << "No" << endl;
    return 0;
  }
  cout << "Yes" << endl;
}
