RecursionBinarySearch.c

#include <stdio.h>
int binarySearch(int arr[], int low, int high, int key) 
{
    if (low > high)
        return -1; 
    int mid = low+(high-low)/2;

    if (arr[mid] == key)
        return mid; // Key found
    else if (arr[mid] > key)
        return binarySearch(arr, low, mid-1, key);
    else
        return binarySearch(arr, mid+1, high, key);
}

int main() {
    int n, key;
    printf("Enter size of array: ");
    scanf("%d", &n);

    int arr[n];
    printf("Enter %d elements in ascending order:\n", n);
    for (int i=0; i < n; i++)
        scanf("%d", &arr[i]);

    printf("Enter element to search: ");
    scanf("%d", &key);

    int result = binarySearch(arr, 0, n-1, key);
    if (result == -1)
        printf("Element not found.\n");
    else
        printf("Element found at location %d.\n", result);
    return 0;
}