#include <bits/stdc++.h>
using namespace std;
int a, x;
char c;
int main() {
  cin >> a >> a;
  if ((cin >> x) && (cin >> c) && (cin >> x)) {
    int cnt = 0;
    do {
      cnt++;
      x /= 10;
    } while (x);
    if (c == '-' && cnt == a) {
      puts("Yes");
      return 0;
    }
  }
  puts("No");
  return 0;
}
