def main():
    import sys
    input = sys.stdin.read().split()
    ptr = 0
    N = int(input[ptr])
    ptr += 1
    M = int(input[ptr])
    ptr += 1

    V = list(map(int, input[ptr:ptr+N]))
    ptr += N

    S = []
    for _ in range(N):
        S.append(input[ptr])
        ptr += 1

    # Compute sum_boxes: sum of V_i compatible with each box j
    sum_boxes = [0] * M
    for j in range(M):
        for i in range(N):
            if S[i][j] == 'o':
                sum_boxes[j] += V[i]

    # Sort boxes by sum in descending order, then by index
    sorted_boxes = sorted([(sum_boxes[j], j) for j in range(M)], key=lambda x: (-x[0], x[1]))

    # Initialize box sums
    box_sum = [0] * M

    for i in range(N):
        v = V[i]
        s_i = S[i]
        for (s, j) in sorted_boxes:
            if s_i[j] == 'o':
                box_sum[j] += v
                break

    # Compute the result
    result = sum(x*x for x in box_sum)
    print(result)

if __name__ == "__main__":
    main()