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