Fraktaali

"""
	Written by, Tuukka Yildirim.
	
	input: n -> [1, 10]
	
	Things I know right off the getgo.
	Area of the fractal = 4 ** (n - 1)
	Side length of the fractal = sqrt(4 ** (n - 1)), where ** denotes exponentiation.
	
	The solution used here is recursive. The fractal matrix that is manipulated
	consists of boolean values. I found it easier to hold the matrix in a 1D list.
	
	The idea for F(n) is to return a 1D list of boolean values that represent
	# and . accordingly [true -> #, false -> .] 	Also, the list should be
	in a form, such that the fractal lines can be easily decoded by reading
	lines of the length sqrt(4 ** (n - 1)). This turned out to be a problem,
	that I solved with some math that can be found at F.
	
	At the end, we just slice the list to form the fractal.
"""
 
 
 
def reverseBlock(arr):
	return [not val for val in arr]
 
from collections import Iterable
 
def flatten(items):
    """Yield items from any nested iterable."""
    for x in items:
        if isinstance(x, Iterable) and not isinstance(x, (str, bytes)):
            yield from flatten(x)
        else:
            yield x
 
 
 
def F(n):
	if n == 1: return [True]
	elif n == 2: return [True, True, True, False]
	else:
		block = F(n - 1)
			
		grid = list(flatten([block, block, block, reverseBlock(block)]))
		#print(grid)
 
		blocks = []
 
		area = 4 ** (n - 1)
		subArea = area // 4
		side = int(area ** 0.5)
 
		for y in range(side):
			# Every row has 2 sides.
			# LLLL | PPPP
			# LLLL | PPPP
			# EEEE | IIII
			# EEEE | IIII
			halfWay = (side // 2)
			if y < halfWay:
				# Upper region
				for x in range(side):
					realX = x % halfWay
					if x < halfWay:
						# Upper left
						blocks.append(grid[y * halfWay + x])
					else:
						# Upper right
						blocks.append(grid[subArea + y * halfWay + realX])
			else:
				# Lower region
				realY = y % halfWay
				for x in range(side):
					realX = x % halfWay
					if x < halfWay:
						# Lower left
						blocks.append(grid[2 * subArea + realY * halfWay + x])
					else:
						# Lower right
						blocks.append(grid[3 * subArea + realY * halfWay + realX])
							
 
		return blocks
 
 
n = int(input())
 
grid = F(n)
 
area = 4 ** (n - 1)
subArea = area // 4
side = int(area ** 0.5)
 
lines = ""
for i in range(side):
	cutStart = i * side
	cutEnd = cutStart + side
	slice = grid[cutStart : cutEnd]
	print("".join([".#"[val] for val in slice]))

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED

Test 3

Group: 3

Verdict: ACCEPTED

Test 4

Group: 4

Verdict: ACCEPTED

Test 5

Group: 5

Verdict: ACCEPTED

Test 6

Group: 6

Verdict: ACCEPTED

Test 7

Group: 7

Verdict: ACCEPTED

Test 8

Group: 8

Verdict: ACCEPTED

Test 9

Group: 9

Verdict: ACCEPTED

Test 10

Group: 10

Verdict: ACCEPTED