二分查找——递归和非递归
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#include <iostream>#include <assert.h>using namespace std;//二分查找,非递归形式int binarySearch(int *a, int b, int e, int v) { assert(a != NULL); int *begin = a+b;int *end = a+e;int *mid; //异常处理 if (!a || b >= e) {return -1; }//折半查找 while (begin < end) { mid = begin + ((end - begin) >> 1); assert(*begin <= *mid && *mid <= *end); if (*mid > v) {end = mid; } else if (*mid < v) {begin = mid + 1; } else {return mid - a; } } return -1; } //递归实现二分查找int BinSearch(int Array[],int low,int high,int key/*要找的值*/){assert(Array != NULL);if (low<=high){int mid = (low+high)>>1;if(key == Array[mid]){return mid;}else if(key<Array[mid]){return BinSearch(Array,low,mid-1,key);}else if(key>Array[mid]){return BinSearch(Array,mid+1,high,key);}}else{return -1;}}void main(){int a[10] = {1,2,3,4,5,6,7,8,9,10};int b = BinSearch(a,0,9,6);cout << b <<endl;}