AtCoDeer is thinking of painting an infinite two-dimensional grid in a checked pattern of side K.
Here, a checked pattern of side K is a pattern where each square is painted black or white so that each connected component of each color is a K × K square.
Below is an example of a checked pattern of side 3:
AtCoDeer has N desires.
The i-th desire is represented by x_i, y_i and c_i.
If c_i is B, it means that he wants to paint the square (x_i,y_i) black; if c_i is W, he wants to paint the square (x_i,y_i) white.
At most how many desires can he satisfy at the same time?

-----Constraints-----
- 1 ≤ N ≤ 10^5
- 1 ≤ K ≤ 1000
- 0 ≤ x_i ≤ 10^9
- 0 ≤ y_i ≤ 10^9
- If i ≠ j, then (x_i,y_i) ≠ (x_j,y_j).
- c_i is B or W.
- N, K, x_i and y_i are integers.

-----Input-----
Input is given from Standard Input in the following format:
N K
x_1 y_1 c_1
x_2 y_2 c_2
:
x_N y_N c_N

-----Output-----
Print the maximum number of desires that can be satisfied at the same time.

-----Sample Input-----
4 3
0 1 W
1 2 W
5 3 B
5 4 B

-----Sample Output-----
4

He can satisfy all his desires by painting as shown in the example above.

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