import sys
input = lambda : sys.stdin.readline().rstrip()

write = lambda x: sys.stdout.write(x+"\n")
debug = lambda x: sys.stderr.write(x+"\n")
writef = lambda x: print("{:.12f}".format(x))


n,m = list(map(int, input().split()))
vs = list(map(int, input().split()))
ns = [[] for _ in range(n)]
ns2 = [[] for _ in range(m)]
vals = [0]*m
for i in range(n):
    s = input()
    for j in range(m):
        if s[j]=="o":
            ns[i].append(j)
            ns2[j].append(i)
            vals[j] += vs[i]
ans = 0
done = [0]*n
for _ in range(m):
    best = (-1, None)
    for j in range(m):
        if vals[j]<=-1:
            continue
        if best[0]<vals[j]:
            best = (vals[j], j)
    v, j = best
#     print(vals, v, j)
    assert j!=-1
    vals[j] = -1
    ans += v*v
    for i in ns2[j]:
        if done[i]:
            continue
        done[i] = 1
        vv = vs[i]
        for jj in ns[i]:
            vals[jj] -= vv
print(ans)