20 20 100 100
AABBAAABAABBBBBAABBB
ABBAABAAABAABBABBBBA
BBAAAABBAAAAAAABBBBA
ABBBAAABBBBBBBBBAAAB
ABABBAAAAABBAAABBAAA
ABBBAABABBABBABAABAA
BABAAABBABAAABBBAABB
ABBABAAABBABBABABAAA
BBAABBAAABABABBBAAAA
AAAAABBABABAABAAAAAA
BAAAABBBAAABABABBBAB
AAABABBABBBABAABABBB
BABBAAAAABAABABBAAAB
AAABABBBBAAABAAAAAAA
ABAAABBAAAAAAAABAAAB
BBABBBBBABABBAABAAAA
BAABAAABAAAABBBAAABA
ABABBAABBABABBBABBBA
BBAAAAABBABAABBBBAAB
BABABBAABAABAAABAABB