Day 1

day01-1.py

@@ -0,0 +1,35 @@
+def main():
+    from string import digits
+
+    with open("input01.txt", "r") as file:
+        input_lines = file.readlines()
+
+    # The calibration value of each line is the first and last digit 
+    # in each line, in order, combined to make a two-digit number.
+    calibrations = []
+    for line in input_lines:
+        line = line.strip()
+        if line == "":
+            continue
+        first = ""
+        last = ""
+        for i, char in enumerate(line):
+            if char in digits:
+                # print(f"Found first digit in {line} at position {i}: {char}")
+                first = char
+                break
+        for i, char in enumerate(line[::-1]):
+            if char in digits:
+                # print(f"Found last digit in {line} at position {len(line) - i}: {char}")
+                last = char
+                break
+        calibrations.append(int(first + last))
+    
+    print(calibrations)
+
+    # The total calibration value is the sum of the individual
+    # calibration values.
+    print(f"Total calibration value: {sum(calibrations)}")
+
+if __name__ == "__main__":
+    main()

day01-2.py

@@ -0,0 +1,71 @@
+DEBUG = False
+DEBUG_PREFIX = ""
+
+def debug(message, *args, **kwargs):
+    if DEBUG:
+        print(f"{DEBUG_PREFIX} {message}", *args, **kwargs)
+
+def main():
+    from string import digits
+
+    DIGITS_SPELLED = ["zero", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine"]
+
+    with open("input01.txt", "r") as file:
+        input_lines = file.readlines()
+
+    # The calibration value of each line is the first and last digit 
+    # in each line, in order, combined to make a two-digit number.
+    calibrations = []
+    for line in input_lines:
+        line = line.strip()
+        if line == "":
+            continue
+        first = ""
+        last = ""
+        spelled_digits = {}
+        first_spelled = len(line) + 1
+        last_spelled = -1
+        for digit in DIGITS_SPELLED:
+            position = 0
+            while position < len(line):
+                debug(f"{position=}", end=" ")
+                if digit in line[position:]:
+                    new_index = line[position:].index(digit)
+                    spelled_digits[new_index + position] = str(DIGITS_SPELLED.index(digit))
+                    position += new_index + 1
+                else:
+                    position = len(line)
+        if len(spelled_digits) > 0:
+            first_spelled = min(spelled_digits.keys())
+            last_spelled = max(spelled_digits.keys())
+        debug(spelled_digits, first_spelled, last_spelled)
+        for i, char in enumerate(line):
+            if char in digits:
+                if i < first_spelled:
+                    debug(f"Found first digit in {line} at position {i}: {char}")     
+                    first = char
+                    break
+                else:
+                    debug(f"Found first digit in {line} at position {first_spelled}: {spelled_digits[first_spelled]}")
+                    first = spelled_digits[first_spelled]
+                    break
+        for i, char in enumerate(line[::-1]):
+            if char in digits:
+                if (len(line) - i) > last_spelled:
+                    debug(f"Found last digit in {line} at position {len(line) - i}: {char}")
+                    last = char
+                    break
+                else:
+                    debug(f"Found last digit in {line} at position {last_spelled}: {spelled_digits[last_spelled]}")
+                    last = spelled_digits[last_spelled]
+                    break
+        calibrations.append(int(first + last))
+    
+    debug(calibrations)
+
+    # The total calibration value is the sum of the individual
+    # calibration values.
+    print(f"Total calibration value: {sum(calibrations)}")
+
+if __name__ == "__main__":
+    main()