#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b;
  cin >> a >> b;
  string s;
  cin >> s;
  if (s[a] == '-') {
    for (int i = 0; i < a; i++) {
      if (s[i] >= 0 && s[i] <= 9) {
        for (int j = a + 1; j < a + b + 1; j++) {
          if (s[j] >= 0 && s[j] <= 9) {
            cout << "Yes" << endl;
            return 0;
          }
        }
      }
    }
  }
  cout << "No" << endl;
  return 0;
}
