Programming Basics Online Pre - Exam - 19 and 20 March 2022 / 06. Substitute

k_number = int(input())
l_number = int(input())
m_number = int(input())
n_number = int(input())

first_number_range = range(k_number, 8 + 1, 1)
second_number_range = range(9, l_number - 1, -1)
third_number_range = range(m_number, 8 + 1, 1)
forth_number_range = range(9, n_number - 1, -1)

valid_change_count = 0
available_valid_change = True

for first_number in first_number_range:
    for second_number in second_number_range:

        if first_number % 2 == 0 and second_number % 2 != 0:

            for third_number in third_number_range:
                for forth_number in forth_number_range:

                    if third_number % 2 == 0 and forth_number % 2 != 0:

                        num_one = str(first_number) + str(second_number)
                        num_two = str(third_number) + str(forth_number)

                        if num_one == num_two:
                            if available_valid_change:
                                print("Cannot change the same player.")

                        else:
                            if valid_change_count >= 6:
                                available_valid_change = False

                            if available_valid_change:
                                print(f"{first_number}{second_number} - {third_number}{forth_number}")
                                valid_change_count += 1