二分查找的递归和非递归
二分查找，这个适用于已经排序好了的数组，没有排序那就先排序，不过要根据实际的情况，要是排序代价很小，这样很好了
/***2.15,在有序数组中查找，利用二分查找的方法**/#include <iostream>using namespace std;/***二分查找(也可以通过递归实现)**/int sort(int *a, int length, int value){int left = 0, right = length - 1;while(left <= right){int center = (left + right)/2;if(value < a[center]){right = center - 1;}else if(value > a[center]){left = center + 1;}else{return center;}}return -1;}//递归形式int sort(int *a, int left, int right, int value){int center = (left + right)/2;//异常时的检测if(left == right && a[center] != value) return -1;//递归查找if(value > a[center]) sort(a, center+1, right, value);else if(value < a[center]) sort(a, left, center-1, value);else return center;}int main(){int a[10] = {2,4,5,6,8,12,32,45,55,65};cout<<"列表："<<endl;for(int i=0; i<10; i++){cout<<a[i]<<" ";}cout<<endl;int v;cin>>v;cout<<"在位置:"<<sort(a, 10, v)<<endl;cout<<"递归在位置:"<<sort(a, 0,9, v)<<endl;}?