20 20 1 1 AAAAAAAAAAAAAAAAAAAA BBBBBBBBBBBBBBBBBBBB CCCCCCCCCCCCCCCCCCCC DDDDDDDDDDDDDDDDDDDD EEEEEEEEEEEEEEEEEEEE FFFFFFFFFFFFFFFFFFFF GGGGGGGGGGGGGGGGGGGG HHHHHHHHHHHHHHHHHHHH IIIIIIIIIIIIIIIIIIII JJJJJJJJJJJJJJJJJJJJ KKKKKKKKKKKKKKKKKKKK LLLLLLLLLLLLLLLLLLLL MMMMMMMMMMMMMMMMMMMM NNNNNNNNNNNNNNNNNNNN OOOOOOOOOOOOOOOOOOOO PPPPPPPPPPPPPPPPPPPP QQQQQQQQQQQQQQQQQQQQ RRRRRRRRRRRRRRRRRRRR SSSSSSSSSSSSSSSSSSSS TTTTTTTTTTTTTTTTTTTT