#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <tuple>
#include <map>
#include <set>
typedef long long ll;
using namespace std;
#define rep(i, n) for (int i = 0; i <= int(n); i++)
#define mod 1000000007

int main()
{
    int A,B;
    cin >> A >> B;
    string s;
    cin >> s;
    bool ans = true;
        if(s[A] == '-'){
            ans = false;
        }
    if(int i = 0; i <= A+B+1; i++){
        if(i == a){
            continue;
        }
        else if(!(s[i] >= '0' && s[i] <= '9')){
            ans = false;
        }
    }
    if(ans){
        cout << "Yes" << endl;
    }else{
        cout << "No" << endl;
    }
}