C++实现递归版二分搜索算法

无聊撸了一个，没啥技术含量，别吐槽。。

#include <iostream>
using namespace std;
int BinarySearch(int* nums,int key,int len);
int search(int* nums,int key,int L,int R);

int main()
{
    int *nums;
    int length;
    int keyNum;
    cout<<"请输入你希望的数字个数："<<endl;
    cin>>length;
    nums = new int[length];
    cout<<"请输入"<<length<<"个数:"<<endl;
    for(int i=0;i<length;i++)
        scanf("%d",&nums[i]);
    cout<<"输入你想找的数字：:"<<endl;
    while(cin>>keyNum){
        int result = BinarySearch(nums,keyNum,length);
        if(!(result==-1))
            cout<<"Position in array is: "<<result<<"
"<<endl;
        else
            cout<<"Failed!"<<endl;
        delete[] nums;
        cout<<"请输入你希望的数字个数:"<<endl;
        cin>>length;
        nums = new int[length];
        cout<<"请输入"<<length<<"个数:"<<endl;
        for(int i=0;i<length;i++)
            scanf("%d",&nums[i]);
        cout<<"输入你想找的数字：:"<<endl;
    }
    return 0;
}

int BinarySearch(int* nums,int key,int len){ //仅作为用户入口
    return search(nums,key,0,len);
}

int search(int* nums,int key,int L,int R){
    int mid = (L+R)/2;
    if(nums[mid]==key) return mid;   //递归基
    if(nums[mid]>key)
        return search(nums,key,L,mid-1);
    else if(nums[mid]<key)
        return search(nums,key,mid+1,R);
    return -1;   //如果失败了返回-1
}

OVER