#71：

$input$

1 1
a
a

output

YES

加个特判

#79:

$input$

10101 100
hztextbzboiqfhveyystikzltdzhtvxvxkenycpdqabwpubmwiygpykjwmntludbpjgyssjzfrlqrodzpqagmywadvkjpqgzgxwq*hztextbzboiqfhveyystikzltdzhtvxvxkenycpdqabwpubmwiygpykjwmntludbpjgyssjzfrlqrodzpqagmywadvkjpqgzgxwqhztextbzboiqfhveyystikzltdzhtvxvxkenycpdqabwpubmwiygpykjwmntludbpjgyssjzfrlqrodzpqagmywadvkjpqgzgxwqhztextbzboiqfhveyystikzltdzhtvxvxkenycpdqabwpubmwiygpykjwmntludbpjgyssjzfrlqrodzpqagmywadvkjpqgzgxwqhztextbzboiqfhveyystikzltdzhtvxvxkenycpdqabwpubmwiygpykjwmntludbpjgyssjzfrlqrodzpqagmywadvkjpqgzgxw...（略）

$output$

NO

WA因：循环最后没加cout<<"NO";

#97:

$input$

2 1
a*
a

$output$

YES

循环次数为输入的字符串的长度