把top=1;改成top=0;就可以找出963
#include <stdio.h>
#define N 15
 main()
 {
     int s[N] = {14,25,36,47,58,69,147,258,369,74,85,96,741,852,963}, i, j, temp, n,a=1;
     int top, bottle, mid, sign;
     char c;

     for ( i = 1; i < N; i++ )
         for ( j = 0; j < N - i; j++ )
             if ( s[j] < s[j + 1] )
             {   
                 temp = s[j];
                 s[j] = s[j + 1];
                 s[j + 1] = temp;
             }
     for ( i = 0; i < N; i++ )
         printf ("%d  ",s[i]);
         printf("\n");


    while (a)
     {
         printf ("input a number:");
         scanf ("%d",&n);
         top = 0;
         bottle = N;
         sign = 1;
         while ( sign == 1 )
         {   
             mid = ( top + bottle ) / 2;   
             if ( n > s[0] || n < s[N - 1] )
             {
                 printf ("the number is not exist");
                 sign = 0;
             }
            
             if(n>s[mid])
             { bottle=mid;
             mid=(top+bottle)/2;
             if(n==s[mid]) { printf ("%d 's number is s[%d]\n",n,mid);
                             break;}
               else if(top==bottle) exit(0);
             }
             if(n<s[mid])
             {     top=mid;
                 mid=(top+bottle)/2;
                 if(n==s[mid]) { printf ("%d 's number is s[%d]\n",n,mid);
                             break;}
                 else if(top==bottle) exit(0);
             }
         }
        
         printf ("continue? 1/0:   ");
         scanf ("%d",&a);
         
            
     }
 }

好了，这是为什么呢？

这个也好用，请教这是为什么？

scanf 的格式化字符中，若出现空白字符，则表示滤去所有空白字符。空格和回车都属于空白字符