#include <bits/stdc++.h>
int main() {
  int a, b, i;
  char s[11];
  scanf("%d%d", &a, &b);
  scanf("%s", s);
  for (i = 0; i < a; i++) {
    if (s[i] != '0' || s[i] != '1' || s[i] != '2' || s[i] != '3' ||
        s[i] != '4' || s[i] != '5' || s[i] != '6' || s[i] != '7' ||
        s[i] != '8' || s[i] != '9') {
      printf("No/n");
      return 0;
    }
  }
  if (s[i] != '-') {
    printf("No/n");
    return 0;
  }
  for (i = 1; i <= b; i++) {
    if (s[a + i] != '0' || s[a + i] != '1' || s[a + i] != '2' ||
        s[a + i] != '3' || s[a + i] != '4' || s[a + i] != '5' ||
        s[a + i] != '6' || s[a + i] != '7' || s[a + i] != '8' ||
        s[a + i] != '9') {
      printf("No/n");
      return 0;
    }
  }
  if (s[a + b + 1] != '\0') {
    printf("No/n");
    return 0;
  }
  printf("Yes\n");
  return 0;
}
