#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using P = pair<int, int>;
int main() {
  int a, b;
  string s;
  cin >> s >> b >> s;
  bool flag = true;
  for (int i = 0; i < a; ++i)
    if (s[i] == '-') flag = false;
  if (s[a] != '-') flag = false;
  for (int i = a + 1; i < a + b + 1; ++i)
    if (s[i] == '-') flag = false;
  if (flag)
    cout << "Yes" << endl;
  else
    cout << "No" << endl;
}
