Binary Search in C++ (University Exam Topic) - Review Program

 #include <iostream>

using namespace std;

int binarySearch(int arr[], int size, int key) {

    int si = 0; 

    int ei = size-1;

    

    while(si <= ei) {

        int mid = si + (ei-si)/2;

        

        if(arr[mid] == key) {

            return mid;

        }

        

        else if(arr[mid] <= key) {

            si = mid+1; // go to right half

        } else {

            ei = mid-1; // go to left half

        }

    }

    

    return -1;

}

int main()

{

    int arr[] = {1, 4, 6, 7};

    int size = sizeof(arr)/sizeof(int);

    cout << binarySearch(arr, size, 6);

    return 0;

}