12.py

coords = {x+1j*y: c for y, r in enumerate(open(0)) for x, c in enumerate(r.strip())}
dir_corners = [.5+.5j, .5-.5j, -.5+.5j, -.5-.5j]
visited = set()

def adjacent(coord, dirs=[1, 1j, -1, -1j]):
    return [coord + d for d in dirs]

def fill_region(c):
    visited.add(c)
    region = [c]
    for adj in adjacent(c):
        if coords.get(adj) == coords[c] and adj not in visited:
            region += fill_region(adj)
    return region

s1 = s2 = 0
for c, char in coords.items():
    if c in visited: continue

    perimeter, corners = 0, set()

    for r in (region := fill_region(c)):
        perimeter += sum(adj not in region for adj in adjacent(r))

        for corner in adjacent(r, dir_corners):
            k = [adj for adj in adjacent(corner, dir_corners) if adj in region]
            if len(k) in [1, 3]:
                corners.add(corner)
            elif abs(k[0] - k[1]) != 1:
                corners |= {corner, corner+0.1}

    s1 += perimeter * len(region)
    s2 += len(corners) * len(region)

print(s1, s2, sep="\n")