Memory Game_While_True

initial_string = input().split()

move_counter = 0
while True:

    command = input()
    if command == "end":
        break

    command_split = command.split()
    index_1 = int(command_split[0])
    index_2 = int(command_split[1])

    move_counter += 1

    if 0 <= index_1 < len(initial_string) and 0 <= index_2 < len(initial_string):
        value_1 = initial_string[index_1]
        value_2 = initial_string[index_2]
        if value_1 == value_2:
            print(f"Congrats! You have found matching elements - {value_1}!")
            initial_string.remove(value_1)
            initial_string.remove(value_2)

        else:
            print(f"Try again!")


    else:
        print(f"Invalid input! Adding additional elements to the board")
        middle_point = int(len(initial_string) // 2)
        for el in range(move_counter):
            initial_string.insert(middle_point, f"-{str(move_counter)}a")

    if len(initial_string) == 0:
        print(f"You have won in {move_counter} turns!")
        break



if len(initial_string) != 0:
    print(f"Sorry you lose :(")
    print(" ".join(initial_string))