二分排序之三行代码

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#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;

}