#include <stdio.h>
 
int main() {
    int arr[100], n, key, low, high, mid, found = 0, i;
 
    // Input number of elements
    printf("Enter number of elements: ");
    scanf("%d", &n);
 
    // Input array elements (must be sorted)
    printf("Enter %d sorted elements (ascending order):\n", n);
    for(i = 0; i < n; i++) {
        scanf("%d", &arr[i]);
    }
 
    // Input element to search
    printf("Enter element to search: ");
    scanf("%d", &key);
 
    // Initialize search boundaries
    low = 0;
    high = n - 1;
 
    // Binary search using loop
    while(low <= high) {
        mid = (low + high) / 2;
 
        if(arr[mid] == key) {
            printf("\nElement %d found at position %d\n", key, mid + 1);
            found = 1;
            break;
        }
        else if(arr[mid] < key)
            low = mid + 1;
        else
            high = mid - 1;
    }
 
    if(!found)
        printf("\nElement %d not found in the array\n", key);
 
    return 0;
}

#include <stdio.h>
 
// Recursive binary search function
int binarySearch(int arr[], int low, int high, int key) {
    if (low > high)
        return -1; // Element not found
 
    int mid = (low + high) / 2;
 
    if (arr[mid] == key)
        return mid;
    else if (arr[mid] > key)
        return binarySearch(arr, low, mid - 1, key);
    else
        return binarySearch(arr, mid + 1, high, key);
}
 
int main() {
    int arr[100], n, key, i, result;
 
    // Input number of elements
    printf("Enter number of elements: ");
    scanf("%d", &n);
 
    // Input sorted array elements
    printf("Enter %d sorted elements (ascending order):\n", n);
    for(i = 0; i < n; i++) {
        scanf("%d", &arr[i]);
    }
 
    // Input search key
    printf("Enter element to search: ");
    scanf("%d", &key);
 
    // Call recursive function
    result = binarySearch(arr, 0, n - 1, key);
 
    if(result != -1)
        printf("\nElement %d found at position %d\n", key, result + 1);
    else
        printf("\nElement %d not found in the array\n", key);
 
    return 0;
}