# Levy Dragon Fractal Curve
# FB - 200912093
from turtle import *
def draw_fractal(length, angle, level, initial_state, target, replacement, target2, replacement2):
state = initial_state
for counter in range(level):
state2 = ''
for character in state:
if character == target:
state2 += replacement
elif character == target2:
state2 += replacement2
else:
state2 += character
state = state2
# draw
for character in state:
if character == 'F':
forward(length)
elif character == '+':
right(angle)
elif character == '-':
left(angle)
if __name__ == '__main__':
draw_fractal(5, 90, 10, 'FX', 'X', 'X+YF+', 'Y', '-FX-Y')