Solve 2021 day 17

2021/d17.py

@@ -0,0 +1,35 @@
+from lib import get_data
+from lib import ints
+
+
+data = get_data(__file__)
+x_min, x_max, y_min, y_max = ints(data)
+
+
+def simulate(x, y, vx, vy):
+    height_max = 0
+    while x <= x_max and y >= y_min:
+        height_max = max(y, height_max)
+        if x_min <= x <= x_max and y_min <= y <= y_max:
+            return True, height_max
+
+        x += vx
+        y += vy
+        if vx != 0:
+            vx = vx - 1 if vx > 0 else vx + 1
+        vy -= 1
+    return False, 0
+
+
+height_max = 0
+total = set()
+for vx in range(1, 2000):
+    for vy in range(-2000, 2000):
+        in_target, height = simulate(0, 0, vx, vy)
+        if in_target:
+            total.add((vx, vy))
+        if in_target and height > height_max:
+            height_max = height
+
+print(height_max)
+print(len(total))

README.md

@@ -188,7 +188,8 @@ Solutions and utility script for Advent of Code challenges in Python.
 - Day 14: 25:52   (Not hard but just too slow.)
 - Day 15: 19:17   (Not that bad. Multiplying the thing threw me off.)
 - Day 16: 50:01   (Way too slow. Was non-trivial but fun. Much better was feasible.)
-- Day 17:
+- Day 17: 21:59   (Not tricky again but struggling for no reason.)
+- Day 18:
 
 ## AoC 2022