Прямоугольнк

_1 = '#'
_0 = '.'
 
def get_bars(s):
    res_bars = set()
    for i in range(len(s)):
        if s[i] == _1:
            if i==0 or s[i-1] == _0:
                L = i
            if i == len(s)-1 or s[i+1] == _0:
                R = i
                res_bars.add((L,R))
    return res_bars
 
def get_rectangles_count(ss_prev, ss, rect, rect_count):
    def bar_is_white(s,L,R):
        return s[L: R+1] == _0 * (R-L+1)
 
    cur_brs = get_bars(ss)
    finish_rect = rect - cur_brs
    rect -= finish_rect
    for L,R in finish_rect:
        rect_count += bar_is_white(ss, L, R)
 
    new_rect = cur_brs - rect
    for L,R in new_rect:
        if not ss_prev or bar_is_white(ss_prev, L, R):
            rect.add((L, R))
    return rect_count
 
n,m = map(int, input('n, m->').split())
rectangles = set()
rectangles_count = 0
s_prev = s = None
 
for i in range(n):
    s_prev = s
    s = input('->')
    rectangles_count = get_rectangles_count(s_prev, s, rectangles, rectangles_count)
print(rectangles_count + len(rectangles))