Code Binary Search

 Code Binary Search

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You have been given a sorted(in ascending order) integer array/list(ARR) of size N and an element X. Write a function to search this element in the given input array/list using 'Binary Search'. Return the index of the element in the input array/list. If the element is not present in the array/list, then return -1.

Input format :

The first line contains an Integer 'N', which denotes the size of the array/list.

The second line contains 'N' single space-separated integers representing the elements in the array/list.

The third line contains the value of X to be searched for in the array/list.

Output Format :

Print the index at which X is present for each test case, -1 otherwise.

Constraints :

0 <= N <= 10^6
0 <= X <= 10^9
Time Limit: 1 sec

Sample Input 1:

7
1 3 7 9 11 12 45
3

Sample Output 1:

1

Sample Input 2:

7
1 2 3 4 5 6 7
9

Sample Output 2:

-1

int binarySearch(int *input, int n, int val)
{
    //Write your code here
    int start=0,end=n-1;
    while(end>=start){
        int mid=start+(end-start)/2;
        if(input[mid]==val)return mid;
        else if(input[mid]>val)end=mid-1;
        else start=mid+1;
    }
    return -1;
}

#include <iostream>
using namespace std;



int binarySearch(int *input, int n, int val)
{
    //Write your code here
    int start=0,end=n-1;
    while(end>=start){
        int mid=start+(end-start)/2;
        if(input[mid]==val)return mid;
        else if(input[mid]>val)end=mid-1;
        else start=mid+1;
    }
    return -1;
}


int main()
{
    // freopen("./Testcases/large/in/input10.txt", "r", stdin);
    // freopen("./Testcases/large/out/output10.txt", "w", stdout);
    int size;
    cin >> size;
    int *input = new int[size];
    for (int i = 0; i < size; ++i)
    {
        cin >> input[i];
    }
    int t = 1;
    // cin >> t;
    while (t--)
    {
        int val;
        cin >> val;
        cout << binarySearch(input, size, val) << endl;
    }
    delete [] input;
    return 0;
}