#include<bits/stdc++.h>
using namespace std;

int main(){
int A,B;
  cin>>A>>B;
  char S(11);
  cin>>S;
  
for(int i=0; i<A; i++){
 if(!('0'<=S[i] && S[i]<='9')){cout<<"No"<<endl;}
}
if(!(S[A]=='-')){cout<<"No"<<endl;}
for(int i=A+1; i<=A+B; i++){
 if(!('0'<=S[i] && S[i]<='9')){cout<<"No"<<endl;}
}  
cout<<"Yes"<<endl;  
}