BinarySearch.c

#include <stdio.h> 
  
//Recursive Method
int binarySearchR(int arr[], int l, int r, int x) 
{ 
    if (r >= l) { 
        int mid = l + (r - l) / 2; 
   
        if (arr[mid] == x) 
            return mid; 
   
        if (arr[mid] > x) 
            return binarySearchR(arr, l, mid - 1, x); 
   
        return binarySearchR(arr, mid + 1, r, x); 
    } 
  
    return -1; 
} 

//Iterative Method
int binarySearchI(int arr[], int l, int r, int x) 
{ 
    while (l <= r) { 
        int m = l + (r - l) / 2; 
  
        if (arr[m] == x) 
            return m; 
  
        if (arr[m] < x) 
            l = m + 1; 
  
        else
            r = m - 1; 
    } 
  
    return -1; 
} 

int main(void) 
{ 
	int n;
	printf("Size : ");
	scanf("%d",&n);
	
    int arr[n];
    
    for(int i=0;i<n;i++)
    scanf("%d",&arr[i]);
    
    int op;
    printf("Enter choice : \n 1. Recursive Method \n 2. Iterative Method ");
    scanf("%d",&op);
    
    int x;
    printf("Value to search : ");
    scanf("%d",&x);
    
    int result;
    
	if(op==1)
    result = binarySearchR(arr, 0, n - 1, x); 
    else 
    result = binarySearchI(arr, 0, n - 1, x);
    
    (result == -1) ? printf("Element is not present in array") : printf("Element is present at index %d", result); 
    return 0; 
}