The Black and White Knights

Problem code: BWKNIGHT

All submissions for this problem are available.

How many ways are there to place a black and a white knight on an N * M chessboard such that they do not attack each other? The knights have to be placed on different squares. A knight can move two squares horizontally and one square vertically, or two squares vertically and one square horizontally. The knights attack each other if one can reach the other in one move.

Input :

The first line contains the number of test cases T. Each of the next T lines contains two integers N and M.

Output :

Output T lines, one for each test case, each containing the required answer for the corresponding test case. 

Sample Input :
3
2 2
2 3
4 5


Sample Output :
12
26
312


Constraints :
1 <= T <= 10000
1 <= N,M <= 100000
Date: 2010-04-10
Time limit: 1s
Source limit: 50000
Languages: C C99 strict C++ 4.0.0-8 C++ 4.3.2 PAS gpc PAS fpc JAVA NICE JAR C# C#2 NEM ST ASM D FORT ADA BASH PERL PYTH RUBY LUA ICON PIKE PHP SCM guile SCM qobi LISP sbcl LISP clisp SCALA HASK ERL CAML CLPS PRLG WSPC BF ICK JS


Comments

Is it possible for the answer

pragrame @ 24 Jul 2010 10:11 PM

Is it possible for the answer to overflow a 64 bit integer?

@ Pradeep : Please ask

syco_adm @ 24 Jul 2010 10:16 PM

@ Pradeep : Please ask questions pertaining to the clarity of the statement only.

If position of knights are

mcsharma1990 @ 24 Jul 2010 10:20 PM

If position of knights are interchanged then will it be considered a diffrent arrangements?

@Mahesh Chandra Sharma yes

syco_adm @ 24 Jul 2010 10:38 PM

@Mahesh Chandra Sharma yes

I'm tring to solve it on

mmirzayanov @ 24 Jul 2010 10:53 PM

I'm tring to solve it on Java, but always get Runtime Error. Main class is "public class Main". It reads from standard input writes to standard output. What is the trick?

Do black knight and white

DylanN @ 24 Jul 2010 11:09 PM

Do black knight and white knight refer to a knight on a black square and a knight on a white square, or is it just to distinguish between the knights?

@Dylan : just to distinguish

syco_adm @ 24 Jul 2010 11:16 PM

@Dylan : just to distinguish between the knights.

@Mike Mirzayanov: Try leaving

anup @ 24 Jul 2010 11:18 PM

@Mike Mirzayanov: Try leaving the input stream open. It will be implicitly closed by the jvm. However, any buffered output stream should be closed/flushed explicitly.


wats o/p for n=1 m=1?

ishandutta2007 @ 24 Jul 2010 11:21 PM

wats o/p for n=1 m=1?

0

syco_adm @ 24 Jul 2010 11:25 PM

0

damn!!!  i missed it.... i

raman bhatia @ 25 Jul 2010 12:10 AM

damn!!!  i missed it....

i thought its on25th :(

I can't cubmit a solution.

anton_postnikov @ 25 Jul 2010 12:10 AM

I can't cubmit a solution. Submit button has the following URL: http://www.codechef.com/COOK01/problems/BWKNIGHT/#.

What is the trouble in?

  Please Tell whether the

theeporithirumugam @ 25 Jul 2010 12:27 AM

 

Please Tell whether the answer will fit in 64 bit or we need bignums in the question itself

we need bignums

Fdg @ 25 Jul 2010 12:42 AM

we need bignums

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