18-1

2024/18/18-1.py

@@ -0,0 +1,58 @@
+import sys
+import networkx as nx
+import matplotlib.pyplot as plt
+
+testing = False
+fewestSteps = sys.maxsize
+
+def printGraph():
+    pos = {point: point for point in map}
+    fig, ax = plt.subplots()
+    nx.draw(g, pos=pos, node_color='k', ax=ax)
+    nx.draw(g, pos=pos, node_size=750, ax=ax, with_labels=True)  # draw nodes and edges
+    ax.set_xlim(-1,width)
+    ax.set_ylim(-1,height)
+    ax.tick_params(left=True, bottom=True, labelleft=True, labelbottom=True)
+    plt.show()
+
+
+if testing:
+    width = height = 7
+    input = '2024/18/testinput.txt'
+    stopAt = 12
+else:
+    width = height = 71
+    input = '2024/18/input.txt'
+    stopAt = 1024
+
+map = {}
+fallingBytes = []
+
+g = nx.Graph()
+directions = [(1, 0), (0, 1), (-1, 0), (0, -1)]
+for i in range(height):
+    for j in range(width):
+        map[i,j] = '.'
+        g.add_node((i,j))
+
+for node in map:
+    x, y = node
+    for direction in directions:
+        dirX, dirY = direction
+        neighbour = (x + dirX, y + dirY)
+        if neighbour in map:
+            g.add_edge(node, neighbour)
+
+with open(input) as f:
+    for i, line in enumerate(f):
+        if i >= stopAt:
+            break
+        line = line.strip().split(',')
+        corruptedNode = (int(line[0]), int(line[1]))
+        fallingBytes.append(corruptedNode)
+        g.remove_node(corruptedNode)
+
+path = nx.shortest_path(g, (0,0), (width-1, height-1))
+
+print(len(path) - 1) # don't count the last step, like the reindeer maze
+

2024/18/testinput.txt

@@ -0,0 +1,25 @@
+5,4
+4,2
+4,5
+3,0
+2,1
+6,3
+2,4
+1,5
+0,6
+3,3
+2,6
+5,1
+1,2
+5,5
+2,5
+6,5
+1,4
+0,4
+6,4
+1,1
+6,1
+1,0
+0,5
+1,6
+2,0