#include <bits/stdc++.h>
int main() {
  int a, b;
  scanf("%d %d", &a, &b);
  char name[15];
  scanf("%s", name);
  int count = 0;
  for (int i = 0; i < strlen(name); i++) {
    if (name[a] == '-') {
      count = count + 1;
    } else {
      count = count + 0;
    }
  }
  if (count == 0) {
    printf("No\n");
  } else {
    printf("Yes\n");
  }
  return 0;
}
