`IP-19.c`¶

Problem Statement

Write a C program that includes a user-defined function named binarySearch with the signature int binarySearch(int arr[], int size, int target);. The function should perform a binary search on a sorted array of integers and return the index of the target element if found, and -1 otherwise.

Metadata¶

Property	Detail
Author	Amit Dutta amitdutta4255@gmail.com
Date	03 Jan 2026
License	MIT License (See the LICENSE file for details)
Difficulty	Intermediate (index: 4 / 10)

Concepts¶

Beta Feature

This concept detection system is still in beta and may occasionally show incorrect or incomplete results.

Binary Search
Array
Iteration
Sorting (possible)
Recursion

Actions¶

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Source Code¶

#include <stdio.h>

int inputArray(int[], int);
// void sortArray(int[], int);
int binarySearch(int[], int, int);

int main()
{
    int size;
    printf("How many element do you want to enter: ");
    scanf("%d", &size);
    int arr[size];
    int target = inputArray(arr, size);
    // sortArray(arr, size); // If needed
    int index = binarySearch(arr, size, target);
    if (index != -1)
    {
        printf("\nElement %d is found at index %d.", target, index);
    }
    else
    {
        printf("\nElement %d is not found.", target);
    }
    return 0;
}

int inputArray(int arr[], int size)
{
    int i, target;
    for (i = 0; i < size; i++)
    {
        printf("Enter element for position %d: ", i);
        scanf("%d", &arr[i]);
    }
    printf("\nEnter the target element: ");
    scanf("%d", &target);
    return target;
}

/* void sortArray(int arr[], int size)
{    
    // using Bubble Sort...

    int tempArr[size], i, j, temp;
    printf("\nBefore Sorting:\n[");
    for (i = 0; i < size; i++)
    {
        printf("%d", arr[i]);
        if (i != size - 1)
        {
            printf(", ");
        }
    }
    printf("]\n");
    for (i = 0; i < size - 1; i++)
    {
        for (j = 0; j < size - i - 1; j++)
        {
            if (arr[j] > arr[j + 1])
            {
                temp = arr[j];
                arr[j] = arr[j + 1];
                arr[j + 1] = temp;
            }
        }
    }
    printf("\nAfter Sorting:\n[");
    for (i = 0; i < size; i++)
    {
        printf("%d", arr[i]);
        if (i != size - 1)
        {
            printf(", ");
        }
    }
    printf("]\n");
}
*/

int binarySearch(int arr[], int size, int target)
{
    int low = 0;
    int high = size - 1;
    int mid;
    while (low <= high)
    {
        mid = low + ((high - low) / 2);
        if (arr[mid] == target)
        {
            return mid;
        }
        else if (arr[mid] > target)
        {
            high = mid - 1;
        }
        else if (arr[mid] < target)
        {
            low = mid + 1;
        }
    }
    return -1;
}

Explanation¶

Explain with AI

Copy the prompt below and paste it into any AI assistant.

    You are explaining a C programming code to a beginner.

    STRICT RULES:

    - Only use the given code. Do NOT assume anything not present.

    - Do NOT add extra examples.

    - Keep explanation clear and short.

    - If something is unclear, say "Not clear from code".

    - Follow the exact format below. Do NOT change headings.

    FORMAT:

    [START]

    ## What it does

    (Explain the overall purpose in 1-2 sentences)

    ## Step-by-step

    (Explain how the code works in steps, simple language)

    ## Key Concepts

    (List concepts like loop, condition, function, etc.)

    ## Notes

    (Mention any limitations, errors, or assumptions)

    [END]

    CODE (IP-19.c):

    #include <stdio.h>

    int inputArray(int[], int);
    // void sortArray(int[], int);
    int binarySearch(int[], int, int);

    int main()
    {
        int size;
        printf("How many element do you want to enter: ");
        scanf("%d", &size);
        int arr[size];
        int target = inputArray(arr, size);
        // sortArray(arr, size); // If needed
        int index = binarySearch(arr, size, target);
        if (index != -1)
        {
            printf("\nElement %d is found at index %d.", target, index);
        }
        else
        {
            printf("\nElement %d is not found.", target);
        }
        return 0;
    }

    int inputArray(int arr[], int size)
    {
        int i, target;
        for (i = 0; i < size; i++)
        {
            printf("Enter element for position %d: ", i);
            scanf("%d", &arr[i]);
        }
        printf("\nEnter the target element: ");
        scanf("%d", &target);
        return target;
    }

    /* void sortArray(int arr[], int size)
    {    
        // using Bubble Sort...

        int tempArr[size], i, j, temp;
        printf("\nBefore Sorting:\n[");
        for (i = 0; i < size; i++)
        {
            printf("%d", arr[i]);
            if (i != size - 1)
            {
                printf(", ");
            }
        }
        printf("]\n");
        for (i = 0; i < size - 1; i++)
        {
            for (j = 0; j < size - i - 1; j++)
            {
                if (arr[j] > arr[j + 1])
                {
                    temp = arr[j];
                    arr[j] = arr[j + 1];
                    arr[j + 1] = temp;
                }
            }
        }
        printf("\nAfter Sorting:\n[");
        for (i = 0; i < size; i++)
        {
            printf("%d", arr[i]);
            if (i != size - 1)
            {
                printf(", ");
            }
        }
        printf("]\n");
    }
    */

    int binarySearch(int arr[], int size, int target)
    {
        int low = 0;
        int high = size - 1;
        int mid;
        while (low <= high)
        {
            mid = low + ((high -
    ... (truncated for brevity)

IP-19.c¶