#include <iostream>
#include <string>
#include <string.h>
#include <cctype>
#include <algorithm>
using namespace std;

bool myStrcmp(string str, int range) {
	if (std::all_of(str.cbegin(), str.cend(), isdigit)) {
		return true;
	}
	return false;
}

int main()
{
	unsigned int A = 0, B = 0;
	cin >> A >> B;
	string str = {};
	cin >> str;
	if ( strcmp(&str[A], "-") && str.size() == A+B+1) {
		if (myStrcmp(str.substr(0, A), A) && myStrcmp( str.substr(A + 1, A + B + 1), A + B + 1)) {
			cout << "Yes" << endl;
			return 0;
		}
	}
	cout << "No" << endl;

    return 0;
}
