#P12022. [USACO25OPEN] Hoof Paper Scissors Minus One B

[USACO25OPEN] Hoof Paper Scissors Minus One B

Description

In a game of Hoof Paper Scissors, Bessie and Elsie can put out one of NN (1N30001 \leq N \leq 3000) different hoof symbols labeled 1N1\dots N, each corresponding to a different material. There is a complicated chart of how the different materials interact with one another, and based on that chart, either:

  • One symbol wins and the other loses.
  • The symbols draw against each other.

Hoof Paper Scissors Minus One works similarly, except Bessie and Elsie can each put out two symbols, one with each hoof. After observing all four symbols that they have all put out, they each choose one of their two symbols to play. The outcome is decided based on normal Hoof Paper Scissor conventions.

Given the MM (1M30001 \leq M \leq 3000) symbol combinations that Elsie plans to make across each game, Bessie wants to know how many different symbol combinations would result in a guaranteed win against Elsie. A symbol combination is defined as an ordered pair (L,R)(L,R) where LL is the symbol the cow plays with her left hoof and RR is the symbol the cow plays with her right hoof. Can you compute this for each game?

Input Format

The first line contains two space-separated integers NN and MM representing the number of hoof symbols and the number of games that Bessie and Elsie play.

Out of the following NN lines of input, the iith line consists of ii characters ai,1ai,2ai,ia_{i,1}a_{i,2}\ldots a_{i,i} where each ai,j{D,W,L}a_{i,j} \in \{\texttt D,\texttt W,\texttt L\}. If ai,j=Da_{i,j} = \texttt D, then symbol ii draws against symbol jj. If ai,j=Wa_{i,j} = \texttt W, then symbol ii wins against symbol jj. If ai,j=La_{i,j} = \texttt L, then symbol ii loses against symbol jj. It is guaranteed that ai,i=Da_{i,i} = \texttt D.

The next MM lines contain two space separated integers s1s_1 and s2s_2 where 1s1,s2N1 \leq s_1,s_2 \leq N. This represents Elsie's symbol combination for that game.

Output Format

Output MM lines where the ii-th line contains the number of symbol combinations guaranteeing that Bessie can beat Elsie in the ii-th game.

3 3
D
WD
LWD
1 2
2 3
1 1
0
0
5

Hint

In this example, this corresponds to the original Hoof Paper Scissors and we can let Hoof=1, Paper=2, and Scissors=3. Paper beats Hoof, Hoof beats Scissors, and Scissors beats Paper. There is no way for Bessie to guarantee a win against the combinations of Hoof+Paper or Paper+Scissors. However, if Elsie plays Hoof+Hoof, Bessie can counteract with any of the following combinations.

  • Paper+Paper
  • Paper+Scissors
  • Paper+Hoof
  • Hoof+Paper
  • Scissors+Paper

If Bessie plays any of these combinations, she can guarantee that she wins by putting forward Paper.

SCORING:
  • Inputs 2-6: N,M100N,M\le 100
  • Inputs 7-12: No additional constraints.