Problem:
Score : 200 points

Problem Statement

The postal code in Atcoder Kingdom is A+B+1 characters long, its (A+1)-th character is a hyphen -, and the other characters are digits from 0 through 9.

You are given a string S. Determine whether it follows the postal code format in Atcoder Kingdom.

Constraints

1≤A,B≤5

|S|=A+B+1

S consists of - and digits from 0 through 9.

Input

Input is given from Standard Input in the following format:

A B
S

Output

Print Yes if S follows the postal code format in AtCoder Kingdom; print No otherwise.

Sample Input 1

3 4
269-6650

Sample Output 1

Yes

The (A+1)-th character of S is -, and the other characters are digits from 0 through 9, so it follows the format.

Sample Input 2

1 1
---

Sample Output 2

No

S contains unnecessary -s other than the (A+1)-th character, so it does not follow the format.

Sample Input 3

1 2
7444

Sample Output 3

No

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include<iostream>
#include<string>
#include<cstdio>
#include<algorithm>
#include<cstdlib>
#include<cmath>
#include<vector>
#include<deque>
#include<queue>
#include<stack>
#include<utility>
#include<array>
#include<cassert>
#include<list>
#include<experimental/any>
#include<cstring>
#include<cctype>
#include<ctime>
#include<cstdbool>
#include<cstdint>
#include<cstddef>
#include<set>
#include<unordered_set>
#include<bitset>
 
using namespace std;
using experimental::any;
 
#define SPEEDY cin.tie(0);ios::sync_with_stdio(false);
 
#define REP(i,n) for(int i=0;i<(n);i++)
#define ARREP(i,n,X) for(int i=0;i<(n);i++)cin>>X[i]
#define FOR(i,X,n) for(int i=(X);i<(n);i++)
#define EREP(i,n) for(int i=1;i<=n;i++)
#define BitFOR(N) REP(Bit,1<<(N))
 
//#define MODE 1
#ifdef MODE
#define DEB(X) cout<< #X <<": "<<X<<" ";
#define DEB2(X) cout<<X<<" ";
#define ARDEB(i,X) cout<< #X <<"["<<i<<"]: "<<X[i]<<" ";
#define TFDEB(f) (f)? cout<<"true ":cout<<"false ";
#define FORDEB(n,X) for(int i=0;i<(n);i++)ARDEB(i,X)
#define END cout<<endl;
#else
#define DEB(X) {}
#define DEB2(X) {}
#define ARDEB(i,X) {}
#define TFDEB(f) {}
#define FORDEB(n,X) {}
#define END {}
#endif
 
typedef long long int ll;
typedef unsigned long long ull;
typedef pair<int,int> P;
#define ALL(X) X.begin(),X.end()
struct edge{int to,cost;};
//struct edge{int from,cost,to;};
struct P2{int x,y;};
#define BIT(Bit,n) bitset<n>(Bit)
#define Endl endl
 
const int MOD7=1000000007;
const int INF=100000000;
const int SET=1000; 

int main(){
	int a,b,count=0,count2=0;
	string s;
	bool f=false;
	cin>>a>>b>>s;
	for(int i=0;i<s.size();i++){
		if(i<a && '0'<=s[i] && s[i]<='9'){
			count++;
		}
		if(s[a]=='-'){
			f=true;
		}
		if(a<i && '0'<=s[i] && s[i]<='9'){
			count2++;
		}
	}
	DEB(count)DEB(count2)
	cout<<((count==a && count2==b && f)?"Yes":"No")<<endl;
	return 0;
}