SoftUni Parking

n = int(input())
people = {}

def check_input(lst: list, num: int):
    return len(lst) >= num

for _ in range(n):
    command = input().split()
    cmd = command[0]
    if cmd == 'register' and check_input(command, 3):
        name = command[1]
        plate = command[2]
        if name in people:
            print(f'ERROR: already registered with plate number {people[name]}')
        else:
            people[name] = plate
            print(f'{name} registered {plate} successfully')
    elif cmd == 'unregister' and check_input(command, 2):
        name = command[1]
        if name not in people:
            print(f'ERROR: user {name} not found')
        else:
            print(f'{name} unregistered successfully')
            del people[name]

[print(f'{x} => {y}') for (x, y) in people.items()]