#include <bits/stdc++.h>
using namespace std;
int main() {
  int A, B;
  string S, X;
  cin >> A >> B >> S;
  X = A + "-" + B;
  if (X[A] == '-') {
    if (X.size() == A + B) {
      cout << "Yes" << endl;
    }
  }
  cout << "No" << endl;
}
