#include <bits/stdc++.h>
using namespace std;
int main(void) {
  string S;
  unsigned int A, B, i = 0;
  cin >> A >> B >> S;
  if (S.size() != (A + B + 1)) {
    cout << "No";
    return 0;
  }
  for (auto c : S) {
    cout << "{" << c << "," << i << "}" << endl;
    if (i == A) {
      if (c != '-') {
        cout << "No";
        return 0;
      }
      i++;
      continue;
    }
    if (!isdigit(c)) {
      cout << "No";
      return 0;
    }
    i++;
  }
  cout << "Yes";
}
