-algorithm-examples/algo-binarysearch at master · alperklc12/-algorithm-examples · GitHub

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def binarySearch(array: list, target: int):
    left = 0
    right = len(array)

    while left <= right:
        mid = (left + right) // 2
        if target == array[mid]:
            return array.index(array[mid])
	    # return mid
        elif target < array[mid]:
            right = mid - 1
        else:
            left = mid + 1
    else:
    	return -1


def binary_search(arr, target):
    return binary_search_helper(arr, target, 0, len(arr) - 1)


def binary_search_helper(arr, target, left, right):
    if left <= right:
        mid = (left + right) // 2
        if target == arr[mid]:
            return mid
        elif target < arr[mid]:
            return binary_search_helper(arr, target, left, mid - 1)
        else:
            return binary_search_helper(arr, target, mid + 1, right)