#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  int a, b, i, j, k, no;
  cin >> a >> b;
  for (i = 0; i < a; i++)
    if (s[i] < '0' || s[i] > '9') no = 1;
  if (s[a] != '-') no = 1;
  for (i = a + 1; i < a + b + 1; i++)
    if (s[i] < '0' || s[i] > '9') no = 1;
  if (no)
    cout << "No" << endl;
  else
    cout << "Yes" << endl;
  return 0;
}
