#include <stdio.h>
void main(){
    int i,n,key;
    printf("22A91A6151\n");
    printf("ENTER THE NUMBER OF ELEMENTS:");
    scanf("%d",&n);
    int a[n];
    printf("ENTER THE ELEMENTS:");
    for(i=0;i<n;i++){
    scanf("%d",&a[i]);
    }
    int low=0,high=n-1;
    printf("ENTER THE ELEMENT TO BE SEARCHED:");
    scanf("%d",&key);
    int flag=binarysearch(a,low,high,key);
    if(flag==-1)
    printf("Search Unsuccessful");
    else 
    printf("Search Successful, Element found at position :%d",flag);
}
int binarysearch(int *a,int low,int high,int key){
    if(low==high)
    {
        if(a[low]==key)
        return low;
        else
        return -1;

    }
    else 
    {
        int mid=low+(high-low)/2;
        if(key==a[mid])
        return mid;
        else if(key>a[mid])
        return binarysearch(a,mid+1,high,key);
        else
        return binarysearch(a,low,mid-1,key);
    }
}