635 B | 635 chars
import sys
from math import sqrt, pi, sin, factorial, ceil, floor
from decimal import Decimal
BLANK = " "
#inp = input
inp = lambda : sys.stdin.readline()[:-1].strip()
mii = lambda x = BLANK : [*map(int,inp().split(x))]
mfi = lambda x = BLANK : [*map(float,inp().split(x))]
ii = lambda : int(inp())
fi = lambda : float(inp())
p = print
def solve():
l = [input() for _ in range(8)]
r = [1] * 8
c = [1] * 8
for i in range(8):
for j in range(8):
if l[i][j] == 'R':
r[i] = 0
c[j] = 0
p(sum(r) * sum(c))
if __name__ == "__main__":
tc = 1
for t in range(1, tc+1):
ret = solve()