r=range(26) for i in r:print(''.join(chr(max(i,x)+65)for x in r))
Standard input is empty
ABCDEFGHIJKLMNOPQRSTUVWXYZ BBCDEFGHIJKLMNOPQRSTUVWXYZ CCCDEFGHIJKLMNOPQRSTUVWXYZ DDDDEFGHIJKLMNOPQRSTUVWXYZ EEEEEFGHIJKLMNOPQRSTUVWXYZ FFFFFFGHIJKLMNOPQRSTUVWXYZ GGGGGGGHIJKLMNOPQRSTUVWXYZ HHHHHHHHIJKLMNOPQRSTUVWXYZ IIIIIIIIIJKLMNOPQRSTUVWXYZ JJJJJJJJJJKLMNOPQRSTUVWXYZ KKKKKKKKKKKLMNOPQRSTUVWXYZ LLLLLLLLLLLLMNOPQRSTUVWXYZ MMMMMMMMMMMMMNOPQRSTUVWXYZ NNNNNNNNNNNNNNOPQRSTUVWXYZ OOOOOOOOOOOOOOOPQRSTUVWXYZ PPPPPPPPPPPPPPPPQRSTUVWXYZ QQQQQQQQQQQQQQQQQRSTUVWXYZ RRRRRRRRRRRRRRRRRRSTUVWXYZ SSSSSSSSSSSSSSSSSSSTUVWXYZ TTTTTTTTTTTTTTTTTTTTUVWXYZ UUUUUUUUUUUUUUUUUUUUUVWXYZ VVVVVVVVVVVVVVVVVVVVVVWXYZ WWWWWWWWWWWWWWWWWWWWWWWXYZ XXXXXXXXXXXXXXXXXXXXXXXXYZ YYYYYYYYYYYYYYYYYYYYYYYYYZ ZZZZZZZZZZZZZZZZZZZZZZZZZZ