#include <stddef.h>

​

int binary_search(int value, const int *arr, size_t length) {

    size_t left = 0;

    size_t right = length - 1;

​

    while (left <= right) {

        size_t mid = left + (right - left) / 2;

​

        if (arr[mid] == value) {

            return mid; // Élément trouvé, retourne son indice

        } else if (arr[mid] < value) {

            left = mid + 1; // Élément recherché dans la moitié droite

        } else {

            right = mid - 1; // Élément recherché dans la moitié gauche

        }

    }

​

    return -1; // Élément non trouvé

}

#include <stdio.h>

int main()

{

    int n;

    printf("enter limit of array :\n");

    scanf("%d", &n);

    int a[n], i,e;

    printf("enter your element :\n");

    for (i = 0; i < n; i++)

    {

        scanf("%d", &a[i]);

    }

    int j,temp;

    for(i=0;i<n;i++){

        for(j=0;j<n-1;j++){

            if(a[j]>a[j+1]){

                temp=a[j];

                a[j]=a[j+1];

                a[j+1]=temp;

            }

        }

    }

    printf("your sorted arrays is :\n");

    for (i = 0; i < n; i++)

    {

        printf("%d\t", a[i]);

    }

    printf("\n");

    int value;

    printf("enter a value that you want to search:\n");

    scanf("%d", &value);

    int low = 0, high = n - 1, mid;

    while (low <= high)

    {

        mid = (low + high) / 2;

        if (value == a[mid])

        {

           return printf("your element has been match of element no. %d",mid+1);

        }

        else if (value < a[mid])

        {

            high = mid - 1;

        }else{

            low =mid+1;

        }

        low++;

    }

    return printf("sorry! not found..");

}

// C program to implement recursive Binary Search

#include <stdio.h>

// A recursive binary search function. It returns

// location of x in given array arr[l..r] is present,

// otherwise -1

int binarySearch(int arr[], int l, int r, int x)

{

    if (r >= l) {

        int mid = l + (r - l) / 2;

        // If the element is present at the middle

        // itself

        if (arr[mid] == x)

            return mid;

        // If element is smaller than mid, then

        // it can only be present in left subarray

        if (arr[mid] > x)

            return binarySearch(arr, l, mid - 1, x);

        // Else the element can only be present

        // in right subarray

        return binarySearch(arr, mid + 1, r, x);

    }

    // We reach here when element is not

    // present in array

    return -1;

}

int main(void)

{

    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);

    (result == -1)

        ? printf("Element is not present in array")

        : printf("Element is present at index %d", result);

    return 0;

}

int bSearch(int arr[], int left, int right, int target) {

    if (right >= left) {

        int mid = left + (right - left) / 2;

        if (arr[mid] == target)

            return mid;

        if (arr[mid] > target)

            return binarySearch(arr, left, mid - 1, target);

        return binarySearch(arr, mid + 1, right, target);

    }

    return -1;

}