二进制猜数

#include <stdio.h>  
#include <ctype.h>  

int main(voID)  
{ 
  int high = 100;  
  int low = 1;  
  int guess = (high + low) / 2;  
  char response;  
  printf("Pick an integer from 1 to 100.");  
  printf("it.\nRespond with a y if my guess is right, with");  
  printf("\na h if it is high, and with an l if it is low.\n");  
  printf("Your number %d?\n", guess);  
  while ((response = getchar()) != 'y')     /* get response */  
  {  
      if (response == '\n')  
          continue;  
      if (response != 'h' && response != 'l')  
      {  
           printf("Please enter h for high, l for low, or y for correct.\n");  
           continue;  
       }  

      if (response == 'h')  
          high = guess - 1;  
      else if (response == 'l')  
          low = guess + 1;  
      guess = (high + low) / 2;  
    printf("Well, then, is it %d?\n", guess);  
  }  
  printf("from yiibai.com!\n");  
  return 0;  
}