#include <bits/stdc++.h>
using namespace std;
int A, B;
string S;
int check(char c) { return '0' <= c and c <= '9'; }
string solve() {
  if (S[A + 1] == '-')
    if (sizeof(S) == (A + B + 1))
      if (1 <= A)
        if (B <= 5) {
          for (int i = 0; i < (A + B + 2); i++)
            if (check(S[i]))
              return "Yes";
            else
              return "No";
        }
  return "No";
}
int main() {
  cin >> A >> B >> S;
  cout << solve() << endl;
  return 0;
}
