二分查找

#include <iostream>using namespace std;int Binary_search(int A[],int n,int k){int left=0,right=n-1;while (left<=right){int middle=(left+right)/2;if (k==A[middle]){return middle;} else if (k>A[middle]){left=middle+1;} else{right=middle-1;}}return 0;}int main(){int A[6]={1,3,4,6,77,45};int x=Binary_search(A,6,4);cout<<(x+1)<<endl;return 0;}