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// C program to implement iterative Binary Search

#include <stdio.h>

// A iterative binary search function. It returns

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

// otherwise -1

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

{

while (l <= r) {

int m = l + (r - l) / 2;

// Check if x is present at mid

if (arr[m] == x)

return m;

// If x greater, ignore left half

if (arr[m] < x)

l = m + 1;

// If x is smaller, ignore right half

else

r = m - 1;

}

// if we reach here, then element was

// not present

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;

}