n, m = map(int, input().split())
v = list(map(int, input().split()))
s_list = [input().strip() for _ in range(n)]

# Precompute count of slimes per box
count = [0] * m
for s in s_list:
    for j in range(m):
        if s[j] == 'o':
            count[j] += 1

# Pair each slime's value with its allowed boxes and sort by value descending
slimes = sorted(zip(v, s_list), key=lambda x: -x[0])

sums = [0] * m

for val, s in slimes:
    allowed = []
    for j in range(m):
        if s[j] == 'o':
            allowed.append(j)
    
    max_gain = -1
    best_j = -1
    max_cnt = -1
    for j in allowed:
        current_sum = sums[j]
        gain = 2 * current_sum * val + val * val
        if gain > max_gain or (gain == max_gain and count[j] > max_cnt):
            max_gain = gain
            best_j = j
            max_cnt = count[j]
    sums[best_j] += val

total = sum(x ** 2 for x in sums)
print(total)