#include<iostream>
#include<string>
using namespace std;

int main(){
  int a, b;
  bool ans = true;
  string s;
  cin >> a >> b >> s;
  for(int i = 0; i < a+b+1; i++){
    if(i == a){
      if(a[i] != '-') ans = false;
    }else{
      ans = false;
      for(char c = '0'; c <= '9'; c++){
        if(a[i] == c) ans = true;
      }
    }
    if(!ans) break;
  }
  if(ans) cout << "Yes" << endl;
  else cout << "No" << emdl;
}