Problem: 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:

cba927b2484fad94fb5ff7473e9aadef.png

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.

Examples

Input

4 3
0 1 W
1 2 W
5 3 B
5 4 B


Output

4


Input

2 1000
0 0 B
0 1 W


Output

2


Input

6 2
1 2 B
2 1 W
2 2 B
1 0 B
0 6 W
4 5 W


Output

4

Solution (in CPP):

Solution:
#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
const int K = 3005;
int x[K][K];
int n,k;
int getsize(int x1,int y1,int x2,int y2){
    return x[x2][y2]-x[x2][y1]-x[x1][y2]+x[x1][y1];
}
int main(){
    scanf("%d%d",&n,&k);
    int a,b,i,j;
    char c;
    for(i = 1; i <= n; i++){
        scanf("%d%d %c",&a,&b,&c);
        a %= (2*k);
        b %= (2*k);
        if(c == 'W')
            b += k;
        x[a%(2*k)+1][b%(2*k)+1]++;
    }
    for(i = 1; i <= 2*k; i++){
        for(j = 1; j <= 2*k; j++){
            x[i][j] = x[i][j]+x[i-1][j]+x[i][j-1]-x[i-1][j-1];
        }
    }
    int ans = 0,sum;
    for(i = 1; i <= k; i++){
        for(j = 1; j <= k; j++){
            sum = getsize(0,0,i,j);
            sum += getsize(i,j,k+i,k+j);
            sum += getsize(k+i,k+j,2*k,2*k);
            sum += getsize(k+i,0,2*k,j);
            sum += getsize(0,k+j,i,2*k);
            sum = max(n-sum,sum);
            ans = max(ans,sum);
        }
    }
    printf("%d\n",ans);
    return 0;
}