#include <stdio.h>

/*

<----------------------------------PROBLEM------------------------------------>

Given a sorted array arr[] of n elements, write a function to search a given

element x in arr[] and return the index of x in the array.

Variables used:

n = total number of elements in array.

arr = array initialized with the input size.

el = element to be searched in the array.

lt = left-most index of the search space.

rt = right-most index of the search space.

*/

int main()

{

int n;

scanf("%d", &n);

int arr[n];

for(int i=0; i<n; i++){

scanf("%d", &arr[i]);

}

int el;

scanf("%d", &el);

int lt=0, rt=n-1;

while(lt<=rt){

// in order to prevent overflow of `int`, it has been written lt + (rt-lt)/2 instead of (lt+rt)/2;

int mid = lt + (rt-lt)/2;

// element is equal to mid, return the index

if(arr[mid]==el){

printf("Element found:)\n");

return 0;

}

// element is larger than mid, then shift search space to right.

else if(arr[mid]<el){

lt=mid+1;

}

// element is smaller than mid, then shift search space to left.

else{

rt=mid-1;

}

}

printf("Element not found:(\n");

return 0;

}