#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  int m;
  string l;
  cin >> n >> m >> l;
  int sum = n + m + 1;
  int flag = 0;
  for (int i = 0; i < sum; i++) {
    if (i < n) {
      for (int j = 0; j <= 9; j++) {
        int aa = l[i] - '0';
        if (aa == j) {
          flag = 1;
        }
      }
      if (flag == 0) {
        cout << "No" << endl;
        break;
      }
    } else if (i == n) {
      if (l[i] != '-') {
        cout << "No" << endl;
        flag = 0;
        break;
      }
    } else {
      for (int j = 0; j <= 9; j++) {
        int aa = l[i] - '0';
        if (aa == j) {
          flag = 1;
        }
      }
      if (flag == 0) {
        cout << "No" << endl;
        break;
      }
    }
  }
  if (flag == 1) {
    cout << "Yes" << endl;
  }
  return 0;
}
