import sys
#input = sys.stdin.readline
#input = sys.stdin.buffer.readline #文字列はダメ
#sys.setrecursionlimit(1000000)
import math
import bisect
#import itertools
#import random
from heapq import heapify, heappop, heappush
from collections import defaultdict 
#from collections import deque
import copy #DeepCopy: hoge = [_[:] for _ in hogehoge]
#from functools import lru_cache
#@lru_cache(maxsize=None)
MOD = pow(10,9) + 7
#MOD = 998244353
#dx = [1,0,-1,0]
#dy = [0,1,0,-1]
#dx8 = [1,1,0,-1,-1,-1,0,1]
#dy8 = [0,1,1,1,0,-1,-1,-1]

def main():
    N,K = map(int,input().split())
    N2 = N * 2
    S = [str(input()) for _ in range(N2)]
    C = [list(map(int,input().split())) for _ in range(N2)]

    black = 0
    PQ = []
    for i in range(N2):
        for j in range(N2):
            heappush(PQ,-C[i][j])
            if S[i][j] == '#':
                black += 1
    
    nokori = black
    ans = 0
    while nokori > 0:
        v = heappop(PQ)
        ans -= v #負の値が入っている
        nokori -= 1

    if black%2 == 1:
        print(ans)
    
    L = []
    for i in range(N2):
        for j in range(N):
            temp = C[i][j] + C[i][N2-1-j]
            L.append(temp)
    L.sort(reverse=True)

    tans = sum(L[:(black//2)]) + K
    ans = max(ans, tans)

    print(ans)


if __name__ == '__main__':
    main()