I have try many of my tests, but I don't know what is wrong in my code. What is test #2, please?

Try this one:

INPUT
10
1 1
10 100
200 400
900 8100
45 285
456 2119
456 2120
456 3456
456 4080
456 4081

OUTPUT
1
No solution
2222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222
9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
14667777
No solution
1334444444444444444444444444444444444445555555555555555555555555555555555555555555555555555555555555
2677777777777777777777777788888888888888888888888888888888888
888999999999999999999999999999999999999999999999999
No solution

Me too. I try the Special test but it's wrong #2 test still.

The #2 test is 100 100 ,or others which the length is 100.

Thank you for your test data!

Thks you bruh. ths s1 and s2 hack me ->(456 2120)