嵌入式 C 面试题1

嵌入式c语言的面试题目：

     1：二分查找:

  #include <stdio.h>  

//二分查找，没有二分排序
//前提是数列是排列好的
/*binsearch : find x in v[0] <= v[1] <= ... <= v[n-1] */  
int binsearch(int x, int v[], int n){  
    int low, high, mid;  

    low = 0;  
    high = n - 1;  

    while ( low <= high ) {  
        mid = (low + high) / 2;  
        if(x < v[mid]){  
            high = mid - 1;  
        }  
        else if(x > v[mid]){  
            low = mid + 1;  
        }  
        else{ /*found match*/  
            return mid;  
        }  
    }  

    return -1;  
}  

int main(){  
    int array[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};  
    int location;  
    int number = 4;  
    location = binsearch(number, array, sizeof(array)/sizeof(int));  
    printf("%d\n", location);  
    return 0;  
}