shower

y2021/p13.py

@@ -0,0 +1,16 @@
+import toolkit
+
+
+dots, instructions = text.split('\n\n')
+dots = {eval(pair) for pair in dots.splitlines()}
+ans1 = None
+for line in instructions.splitlines():
+    axis, zz = line.split()[-1].split('=')
+    zz = int(zz)
+    if axis == 'x':
+        dots = {(x, y) if x < zz else (2 * zz - x, y) for x, y in dots}
+    elif axis == 'y':
+        dots = {(x, y) if y < zz else (x, 2 * zz - y) for x, y in dots}
+    if ans1 is None:
+        ans1 = len(dots)
+ans2 = '\n' + toolkit.render({complex(*k): '#' for k in dots})