Advent of Code 2023-25a

```import networkx as nx
import matplotlib.pyplot as plt
import re
floppy = open("input25.txt", mode='r', encoding='utf-8')
thing =  floppy.readlines()
floppy.close()
sourcenode = []

for i, word in enumerate(thing):
sourcenode.append(word[0:3])
thing[i] = word[4:].split()

visual = []
for i, source in enumerate(sourcenode):
for dest in thing[i]:
visual.append([source,dest])
G = nx.Graph()
G.add_edges_from(visual)

nx.draw_networkx(G)
plt.show()
```
```import networkx as nx
import matplotlib.pyplot as plt

G = nx.Graph()
G.add_edges_from([['a','b'],['b','c'],['a','c'],['s','u']])
nx.draw_networkx(G)
plt.show()
```

Koch’s Snowflake in Python

```# Draw a Koch snowflake
from turtle import *

def koch(a, order):
if order > 0:
for t in [60, -120, 60, 0]:
forward(a/3)
left(t)
else:
forward(a)

# Test
koch(100, 0)
pensize(3)
koch(100, 1)
```

Now, we make a small change to the function koch:

```    for t in [60, -120, 60, 0]:
koch(a/3, order-1)
left(t)
```

Completed code:

```# Choose colours and size
color("sky blue", "white")
bgcolor("black")
size = 400
order = 0

# Ensure snowflake is centred
penup()
backward(size/1.732)
left(30)
pendown()

# Make it fast
tracer(100)
hideturtle()

begin_fill()

# Three Koch curves
for i in range(3):
koch(size, order)
right(120)

end_fill()

# Make the last parts appear
update()
```

Source.