Monikulmio

def c(polygon, point):
    x, y = point
    n = len(polygon)
    inside = False
    for i in range(n):
        x1, y1 = polygon[i]
        x2, y2 = polygon[(i + 1) % n]
        if y > min(y1, y2):
            if y <= max(y1, y2):
                if x <= max(x1, x2):
                    if y1 != y2:
                        x_intersect = (y - y1) * (x2 - x1) / (y2 - y1) + x1
                    if x1 == x2 or x <= x_intersect:
                        inside = not inside
    return inside

n, m, k = map(int, input().split())
a = []
for _ in range(k):
    y, x = map(int, input().split())
    a.append((x - 1, y - 1)) 

b = [['.' for _ in range(m)] for _ in range(n)]

for x, y in a:
    b[y][x] = '*'

for i in range(k):
    x1, y1 = a[i]
    x2, y2 = a[(i + 1) % k] 

    dy = y2 - y1
    dx = x2 - x1

    if dx == 0: 
        step = 1 if dy > 0 else -1
        for y in range(y1, y2 + step, step):
            if b[y][x1] == '.':
                b[y][x1] = '|'
    elif dy == 0:
        step = 1 if dx > 0 else -1
        for x in range(x1, x2 + step, step):
            if b[y1][x] == '.':
                b[y1][x] = '='
    elif abs(dx) == abs(dy):
        step_y = 1 if dy > 0 else -1
        step_x = 1 if dx > 0 else -1
        y, x = y1, x1
        while y != y2 or x != x2:
            y += step_y
            x += step_x
            if b[y][x] == '.':
                if dx > 0 and dy > 0:
                    b[y][x] = '\\'
                elif dx > 0 and dy < 0:
                    b[y][x] = '/'
                elif dx < 0 and dy > 0:
                    b[y][x] = '/'
                elif dx < 0 and dy < 0:
                    b[y][x] = '\\'

for y in range(n):
    for x in range(m):
        if b[y][x] == '.':
            if c(a, (x, y)):
                b[y][x] = '#'

for row in b:
    print(''.join(row))

Test 1 (public)

Verdict: ACCEPTED

Test 2 (public)

Verdict: ACCEPTED

Test 3 (public)

Verdict: ACCEPTED

Test 4 (public)

Verdict: ACCEPTED

Test 5 (public)

Verdict: ACCEPTED

Test 6 (public)

Verdict: ACCEPTED

Test 7 (public)

Verdict: ACCEPTED

Test 8 (public)

Verdict: ACCEPTED

Test 9 (public)

Verdict: ACCEPTED

Test 10 (public)

Verdict: ACCEPTED