Solve day 1

01/puzzle.py

@@ -0,0 +1,67 @@
+import re
+
+pt_1_first_digit_pattern = re.compile("([0-9])")
+pt_1_last_digit_pattern = pt_1_first_digit_pattern
+pt_1_symbol_map = {str(n): str(n) for n in range(10)}
+
+pt_2_first_digit_pattern = re.compile(
+    "([0-9]|one|two|three|four|five|six|seven|eight|nine|zero)"
+)
+pt_2_last_digit_pattern = re.compile(
+    "([0-9]|eno|owt|eerht|ruof|evif|xis|neves|thgie|enin|orez)"
+)
+pt_2_symbol_map = {
+    **pt_1_symbol_map,
+    "one": "1",
+    "two": "2",
+    "three": "3",
+    "four": "4",
+    "five": "5",
+    "six": "6",
+    "seven": "7",
+    "eight": "8",
+    "nine": "9",
+    "zero": "0",
+}
+
+
+def _solve(
+    input: list[str],
+    first_digit_pattern: re.Pattern,
+    last_digit_pattern: re.Pattern,
+    symbol_map: dict[str, str],
+) -> int:
+    total = 0
+
+    for line in input:
+        first_digit_match = first_digit_pattern.search(line)
+        last_digit_match = last_digit_pattern.search(line[::-1])
+
+        if not first_digit_match or not last_digit_match:
+            raise ValueError(f'Line "{line}" calibration document contains no digits.')
+
+        first_digit = symbol_map[first_digit_match.group(1)]
+        last_digit = symbol_map[last_digit_match.group(1)[::-1]]
+
+        line_calibration_number = int(first_digit + last_digit)
+        total += line_calibration_number
+
+    return total
+
+
+def solve_pt_1(input: list[str]) -> int:
+    return _solve(
+        input,
+        pt_1_first_digit_pattern,
+        pt_1_first_digit_pattern,
+        pt_1_symbol_map,
+    )
+
+
+def solve_pt_2(input: list[str]) -> int:
+    return _solve(
+        input,
+        pt_2_first_digit_pattern,
+        pt_2_last_digit_pattern,
+        pt_2_symbol_map,
+    )