#include<stdio.h>
int search(int array[],int i);
int main()
{
    int i,j,result;
    int array[10]={1,2,3,4,5,6,7,8,9,10};
    
    printf("please enter the number you want to search");
    while(1){
        scanf("%d",&i);
        if(i<1||i>10){
            printf("please enter the number from 1 to 10");
        }else{
            break;
        }
    result=search(array,i);
    printf("the result is %d",result);
    return 0;
}
int search(int array[],int i)
{
    int mid,low,upper;
    low=0;
    upper=10;
    
    mid=(low+upper)/2;
    while(low<upper){
        if(array[mid]==i)
            return mid;
        else if(array[mid]>i)
            upper=mid-1;
        else
            low=mid+1;
        mid=(low+upper)/2;
    }
}
调试时总是显示 mid low upper 未声明，是什么原因啊？？

#include<stdio.h>
int search(int array[],int i);
int main()
{
    int i,j,result;
    int array[10]={1,2,3,4,5,6,7,8,9,10};
   
    printf("please enter the number you want to search");
    while(1){
        scanf("%d",&i);
        if(i<1||i>10){
            printf("please enter the number from 1 to 10");
        }else{
            break;
        }
     }  /*循环少了 }  */
    result=search(array,i);
    printf("the result is %d",result);
    return 0;
}
int search(int array[],int i)
{
    int mid,low,upper;
    low=0;
    upper=10;
   
    mid=(low+upper)/2;
    while(low<upper){
        if(array[mid]==i)
            return mid;
        else if(array[mid]>i)
            upper=mid-1;
        else
            low=mid+1;
        mid=(low+upper)/2;
    }
}

哦。。。。。我说呢。不过为什么会报那种错误呢？？？

循环体不全while(1)
        {
        scanf("%d",&i);
        if(i<1||i>10)
        {
            printf("please enter the number from 1 to 10");
        }
        else
        {
            break;
        }
    }   
/*你看少了最后的 } 循环体能成立吗? */

不成立，得教了。谢了哈。