BinarySearch.c

#include <stdio.h>

int binarySearch(int arr[], int left, int right, int x) {
    while (left <= right) {
        int mid = left + (right - left) / 2;
        // Check if x is present at mid
        if (arr[mid] == x) {
            return mid;
        }
        // If x greater, ignore left half
        if (arr[mid] < x) {
            left = mid + 1;
        }
        // If x is smaller, ignore right half
        else {
            right = mid - 1;
        }
    }
    // If we reach here, then element was not present
    return -1;
}

int main() {
    int arr[] = {2, 3, 4, 10, 40};
    int n = sizeof(arr) / sizeof(arr[0]);
    int x = 10;
    int result = binarySearch(arr, 0, n - 1, x);
    if (result == -1) {
        printf("Element is not present in array");
    }
    else {
        printf("Element is present at index %d", result);
    }
    return 0;
}