#include <bits/stdc++.h>
using namespace std;
const int N = 15;
char str[N];
int a, b;
int main() {
  bool t1 = false, t2 = false;
  scanf("%d%d", &a, &b);
  scanf("%s", &str + 1);
  int t = strlen(str);
  for (int i = 1; i <= t; i++) {
    if (str[i] >= 48 && str[i] <= 57) t1 = true;
    if (str[a + 1] == '-') t2 = true;
  }
  if (t1 && t2)
    cout << "Yes" << endl;
  else
    cout << "No" << endl;
  return 0;
}
