Solve 2018 day 21, 2020 day 12 and improve 2022 day 19

2020/d12.py

@@ -0,0 +1,82 @@
+from lib import get_data
+
+DIRS = {
+    "N": (-1, 0),
+    "E": (0, 1),
+    "S": (1, 0),
+    "W": (0, -1),
+}
+
+
+def part_1(data):
+    dir_key = "E"
+    pos = 0, 0
+    dirs = "NESW"
+
+    for line in data.splitlines():
+        c = line[0]
+        v = int(line[1:])
+        if c in DIRS.keys():
+            pos = pos[0] + v * DIRS[c][0], pos[1] + v * DIRS[c][1]
+        elif c == "F":
+            dir = DIRS[dir_key]
+            pos = (pos[0] + v * dir[0], pos[1] + v * dir[1])
+        elif c == "R":
+            assert v % 90 == 0
+            dir_key = dirs[(dirs.index(dir_key) + v // 90) % len(dirs)]
+        elif c == "L":
+            assert v % 90 == 0
+            dir_key = dirs[(dirs.index(dir_key) - v // 90) % len(dirs)]
+        else:
+            print(c, v)
+            assert False
+    print(sum(map(abs, pos)))
+
+
+def part_2(data):
+    way_point = (-1, 10)
+    pos = 0, 0
+
+    for line in data.splitlines():
+        c = line[0]
+        v = int(line[1:])
+        if c in DIRS.keys():
+            way_point = way_point[0] + v * DIRS[c][0], way_point[1] + v * DIRS[c][1]
+        elif c == "F":
+            pos = (pos[0] + v * way_point[0], pos[1] + v * way_point[1])
+        elif c == "R":
+            row, col = way_point
+            if v == 90:
+                way_point = (col, -row)
+            elif v == 180:
+                way_point = (-row, -col)
+            elif v == 270:
+                way_point = (-col, row)
+            else:
+                print(c, v)
+                assert False
+        elif c == "L":
+            row, col = way_point
+            if v == 90:
+                way_point = (-col, row)
+            elif v == 180:
+                way_point = (-row, -col)
+            elif v == 270:
+                way_point = (col, -row)
+            else:
+                print(c, v)
+                assert False
+        else:
+            print(c, v)
+            assert False
+    print(sum(map(abs, pos)))
+
+
+def main():
+    data = get_data(__file__)
+    part_1(data)
+    part_2(data)
+
+
+if __name__ == "__main__":
+    main()