python_practice/binary_search.py at main · SawdaDevs/python_practice · GitHub

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def binary_search(input_array, value):
    # can I do this recursively? Yes, but how
    index_to_go = int(len(input_array)/2)

    end_array = len(input_array)
    start_array = 0
    print('Ind start',  index_to_go)
    print('\n')
    while (len(input_array[start_array:end_array]) > 1 and input_array[index_to_go] != value):
        if input_array[index_to_go] < value:  # go to this index
            start_array = index_to_go  # new sub array starts at this array
            index_to_go = int((start_array+end_array)/2)
            print(' new ind to go ', index_to_go,
                  'st:', start_array, 'end:', end_array)
            print(input_array[start_array:end_array])
        elif input_array[index_to_go] > value:
            end_array = index_to_go  # new sub array ends at this array
            index_to_go = int((start_array+end_array)/2)
            print(' new ind to go ', index_to_go,
                  'st:', start_array, 'end:', end_array)
            print(input_array[start_array:end_array])

        if input_array[index_to_go] == value:  # value is the same
            return index_to_go
    return -1


test_list = [1, 3, 9, 11, 15, 19, 29]
test_val1 = 25
test_val2 = 15
print(binary_search(test_list, test_val1))
print(binary_search(test_list, test_val2))