#include <bits/stdc++.h>
using namespace std;
using ll = long long;
void solve() {
  int a, b;
  cin >> a >> b;
  string s;
  for (int i = 0; i < a; i++) {
    if (s[i] < '0' || s[i] > '9') {
      cout << "No" << endl;
      return;
    }
  }
  if (s[a] != '-') {
    cout << "No" << endl;
    return;
  }
  for (int i = a + 1; i < a + b + 1; i++) {
    if (s[i] < '0' || s[i] > '9') {
      cout << "No" << endl;
      return;
    }
  }
  cout << "Yes" << endl;
}
signed main() { solve(); }
