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## Discussion of Problem 1411. 40 Islands Knights

WA42(1411) 40 Islands
Posted by svr 18 Jan 2007 11:31
Fine problem but unexpected WA42.
It may be bug of judj validator also
because of very many ways to build right net and therefore
using undirect verification of our answers.
My prog gives
1. n<3 or m<3-Imaginary
2. n=2*k+1 and m=2*l+1- Imaginary
3. n==3 and m<=7-Imaginary
4. n<=7 and m==3- Imaginary
5. Other cases: Regular and symmetric pictures
with obvious correctness
Soon I will use Inverse program 40 Islands -1419
Re: WA42(1411) 40 Islands
Posted by svr 18 Jan 2007 11:35
svr wrote 18 January 2007 11:31
Fine problem but unexpected WA42.
It may be bug of judj validator also
because of very many ways to build right net and therefore
using undirect verification of our answers.
My prog gives
1. n<3 or m<3-Imaginary
2. n=2*k+1 and m=2*l+1- Imaginary
3. n==3 and m<=7-Imaginary
4. n<=7 and m==3- Imaginary
5. Other cases: Regular and symmetric pictures
with obvious correctness
Soon I will use Inverse program 40 Islands -1419
Soon I will use Inverse program 40 Islands -1419(I have Ac)
as validator of my own
and my suspictions will be confirmed
Re: WA42(1411) 40 Islands
Posted by svr 19 Jan 2007 22:28
Have WA42 But MyAC 1419 Inverse Program
confirms all
answers in range n,m in [1..50]
Re: WA42(1411) 40 Islands
Posted by svr 19 Jan 2007 22:51
Eecuse me. Have ac Now Wa42=7*6. Was bug. And Ac 1419
said this but I talked wrong.
Re: WA42(1411) 40 Islands
Posted by Jerry 18 Aug 2007 07:46