#include <bits/stdc++.h>
using namespace std;
int main() {
  unsigned int A = 0, B = 0;
  cin >> A >> B;
  string str = NULL;
  cin >> str;
  if (strcmp(&str[A], "-")) {
    cout << "Yes" << endl;
  } else {
    cout << "No" << endl;
  }
  return 0;
}
