#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b;
  string s;
  cin >> a >> b;
  cin >> s;
  bool k = 0;
  for (int i = 0; i < a + b + 1; i++) {
    if (s[a] == '-' &&
        (s[i] == '0' || s[i] == '1' || s[i] == '2' || s[i] == '3' ||
         s[i] == '4' || s[i] == '5' || s[i] == '6' || s[i] == '7' ||
         s[i] == '8' || s[i] == '9')) {
      k = 1;
    } else {
      k = 0;
    }
  }
  if (k == 1) printf("Yes\n");
  if (k == 0) printf("No\n");
  return 0;
}
