二分排序之三行代码

 
#include<stdio.h>  
#include<stdlib.h> 
 int a[]={10,22,42,51,56,63,78,99,102,118};  
 int binSearch(int* a, int begin, int end, int k){  
    int mid = begin + ( (end - begin)>>1 ),index;  
    index = a[mid] < k && begin + 1 < end ? binSearch(a,mid+1,end,k) :   
          ( a[mid] > k && begin + 1 < end ? binSearch(a,begin,mid,k) :   
            mid * (a[mid] == k) + (a[mid] != k)*(-1));  
    return index;      
}   
int  main() {  
    int result = binSearch(a,0, sizeof(a)/sizeof(int), 22);  
    printf("%d\n",result);  
    
    return 0;
}