📊📚Intermediate

Search Element in Array (Binary Search)

Search in sorted array

Binary Search efficiently finds an element in a sorted array by repeatedly dividing the search interval in half. Time complexity: O(log n).

Program Code

binary_search.c

1#include <stdio.h>
2
3int binarySearch(int arr[], int n, int target) {
4    int left = 0, right = n - 1;
5    
6    while (left <= right) {
7        int mid = left + (right - left) / 2;
8        
9        if (arr[mid] == target)
10            return mid;       // Found
11        else if (arr[mid] < target)
12            left = mid + 1;   // Search right half
13        else
14            right = mid - 1;  // Search left half
15    }
16    return -1;  // Not found
17}
18
19int main() {
20    int arr[] = {2, 5, 8, 12, 16, 23, 38, 56, 72, 91};
21    int n = sizeof(arr) / sizeof(arr[0]);
22    int target;
23    
24    printf("Array: ");
25    for (int i = 0; i < n; i++) printf("%d ", arr[i]);
26    printf("\n");
27    
28    printf("Enter element to search: ");
29    scanf("%d", &target);
30    
31    int result = binarySearch(arr, n, target);
32    
33    if (result != -1)
34        printf("Found at index %d\n", result);
35    else
36        printf("Element not found\n");
37    
38    return 0;
39}