题解 | #禁止重复注册#

import sys

#用户名的比较不区分大小写
current_users=['Niuniu','Niumei','GURR','LOLO']
new_users=['GurR','Niu Ke Le','LoLo','Tuo Rui Chi']
flag=0
for i in range(len(new_users)):
    flag=0
    for j in current_users:
        if new_users[i].lower()==j.lower():
            print(f'The user name {new_users[i]} has already been registered! Please change it and try again!')
            flag=1
            break
    if flag==0:
        print(f'Congratulations, the user name {new_users[i]} is available!')


for line in sys.stdin:
    a = line.split()
    print(int(a[0]) + int(a[1]))