What's wrong with this code for BinarySearch?

Question

This is the python Binary Search code and when I run it doesn't work.

# Binary Search

def BinarySearch(*args, key, size):
    low = 0
    high = size - 1
    while low <= high:
        mid = (low + high) / 2
        if key < args[mid]:
            high = mid - 1
        else:
            if key > args[mid]:
                low = mid + 1
            else:
                return mid + 1
    return -1

arraySize = 10
A = [num * 2 for num in range(10)]
print("Numbers in array are : ", A)
searchKey = input("Enter integer search key : ")
element = BinarySearch(A, searchKey, arraySize)
if element != -1:
    print("Found value in element : ", element)
else:
    print("Value not found.") 

The error is like this:

TypeError: BinarySearch() missing 2 required keyword-only arguments: 'key' and 'size' So, What's wrong with it?Please help:)

Answer 1

There are multiple errors in your program.

1. You have to place the *args and **args after the positional and keyword arguements.

2. Lets say you have modified the function definition. Now it will convert the array into a tuple which won't work either as per your algo.it wil convert the list to tuple of lists.

       def BinarySearch( key, size,*args):
             pass
   
       [] -> ([], )   
   

3.So, you need to place only the array part.Refer the below code.

    # Binary Search

def BinarySearch(arr, key, size):
    print(args)
    low = 0
    high = size - 1
    while low <= high:
        mid = (low + high) // 2
        if key < args[mid]:
            high = mid - 1
        else:
            if key > args[mid]:
                low = mid + 1
            else:
                return mid + 1
    return -1

arraySize = 10
A = [num * 2 for num in range(10)]
print("Numbers in array are : ", A)
searchKey = input("Enter integer search key : ")
element = BinarySearch(A, int(searchKey), arraySize)
if element != -1:
    print("Found value in element : ", element)
else:
    print("Value not found.")