C++ program to implement binary search using recursion

Here is a C++ program to implement binary search using recursion


 SOURCE CODE OUTPUT

#include<iostream>
#include<math.h>
using namespace std;
int binary(int (&a)[20],int low,int high,int key)
{
    int mid=(low+high)/2;
    if(low>high)
        return -1;
    else if(a[mid]==key)
        return mid;
    else if(key>a[mid])
        binary(a,mid+1,high,key);
    else
        binary(a,low,mid-1,key);
}
int main()
{
    int result,n,a[20],key;
    cout<<"How many numbers to be entered ";
    cin>>n;
    cout<<"Enter number : ";
    for(int i=0;i<n;i++)
         cin>>a[i];
    cout<<"Enter element to be searched : ";
    cin>>key;
    result=binary(a,0,n-1,key);
    if(result==-1)
        cout<<"Element is not found";
    else
        cout<<"Element is found at "<<result+1<<" position ";
    return 0;
}

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