**Note: The time limit for this problem is 3s, 1.5x the default.**
In a game of Hoof Paper Scissors, Bessie and Elsie can put out one of N (1≤N≤3000) different hoof symbols labeled 1…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 M(1≤M≤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) where L is the symbol the cow plays with her left hoof and R is the symbol the cow plays with her right hoof. Can you compute this for each game?
INPUT FORMAT (input arrives from the terminal / stdin):
The first line contains two space-separated integers N and M representing the number of hoof symbols and the number of games that Bessie and Elsie play.
Out of the following N lines of input, the ith line consists of i characters ai,1ai,2…ai,i where each ai,j∈{D,W,L}. If ai,j=D, then symbol i draws against symbol j. If ai,j=W, then symbol i wins against symbol j. If ai,j=L, then symbol i loses against symbol j. It is guaranteed that ai,i=D.
The next M lines contain two space separated integers s1 and s2 where 1≤s1,s2 ≤N. This represents Elsie's symbol combination for that game.
OUTPUT FORMAT (print output to the terminal / stdout):
Output M lines where the i-th line contains the number of symbol combinations guaranteeing that Bessie can beat Elsie in the i-th game.
SAMPLE INPUT:
3 3
D
WD
LWD
1 2
2 3
1 1
SAMPLE OUTPUT:
0
0
5
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,M≤100
Inputs 7-12: No additional constraints.
Problem credits: Suhas Nagar
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