c_对分查找

#include "stdio.h"typedef int ElementType;enum{NotFind = -2,Error = -1,};int main(){ElementType a[]={0,1,2,3,4,6,7,8,9,10};int size = sizeof(a)/sizeof(a[0]);int iRet = BinarySearch(a, 6, size);printf("search 6 ,pos: %d\n",iRet);iRet = BinarySearch(a, -2, size);printf("search -2 ,pos: %d\n",iRet);iRet = BinarySearchRecursion(a, 6, 0, size);printf("recursion search 6 ,pos: %d\n",iRet);iRet = BinarySearch(a, -2, 0, size);printf("recursion search -2 ,pos: %d\n",iRet);iRet = BinarySearchRecursion(a, 5, 0, size);printf("recursion search 5 ,pos: %d\n",iRet);return iRet;}int BinarySearchRecursion(const ElementType *a, ElementType x, int Low, int High){ElementType Mid = (Low+High)/2;if(Low == High){return Error;}if(*(a+Mid) < x){return BinarySearchRecursion(a,x,++Mid,High);}else if(*(a+Mid) > x){return BinarySearchRecursion(a,x,Low,--Mid);}return Mid;}int BinarySearch(const ElementType *a, ElementType x, int size){ElementType Low,Mid,High;Low = 0;High = size - 1;if(x > *(a+High) || x < *(a+Low)){printf("High:%d,Low:%d---->\n", *(a+High), *(a+Low));return Error;}while(Low <= High){Mid = (Low+High)/2;if(*(a+Mid) < x){Low = ++Mid;}else if(*(a+Mid) > x){High = --Mid;}else{return Mid;}}return NotFind;}