Day 10

10/10.py

@@ -0,0 +1,85 @@
+import sys
+
+
+class InvalidChar(Exception):
+    pass
+
+
+PAIRS = {
+    ")": "(",
+    "]": "[",
+    "}": "{",
+    ">": "<",
+}
+
+SCORE_ONE = {
+    ")": 3,
+    "]": 57,
+    "}": 1197,
+    ">": 25137,
+}
+
+SCORE_TWO = {
+    "(": 1,
+    "[": 2,
+    "{": 3,
+    "<": 4,
+}
+
+
+def part_one(lines: list[str]) -> int:
+    score = 0
+    for line in lines:
+        try:
+            stack = []
+            for char in list(line):
+                # Open backets
+                if char in PAIRS.values():
+                    stack.append(char)
+
+                # Close brackets
+                elif char in PAIRS:
+                    top = stack.pop()
+                    if top != PAIRS[char]:
+                        score += SCORE_ONE[char]
+                        raise InvalidChar
+        except InvalidChar:
+            pass
+    return score
+
+
+def part_two(lines: list[str]) -> int:
+    scores = []
+    for line in lines:
+        score = 0
+        try:
+            stack = [None]
+            for char in list(line):
+                # Open backets
+                if char in PAIRS.values():
+                    stack.append(char)
+
+                # Close brackets
+                elif char in PAIRS:
+                    top = stack.pop()
+                    if top != PAIRS[char]:
+                        raise InvalidChar
+
+            # Check not closed brackets
+            while top := stack.pop():
+                score = score * 5 + SCORE_TWO[top]
+
+            scores.append(score)
+        except InvalidChar:
+            pass
+
+    scores.sort()
+
+    return scores[len(scores) // 2]
+
+
+if __name__ == "__main__":
+    lines = sys.stdin.readlines()
+
+    print("Part one:", part_one(lines))
+    print("Part two:", part_two(lines))