aoc2023/solve.py

#!/usr/bin/env python3
import sys
import re

num_values = dict(
    on="1",
    tw="2",
    thre="3",
    four="4",
    fiv="5",
    six="6",
    seve="7",
    eigh="8",
    nin="9",
)

nums_re = r"on(?=e)|tw(?=o)|thre(?=e)|four|fiv(?=e)|six|seve(?=n)|eigh(?=t)|nin(?=e)|1|2|3|4|5|6|7|8|9"

sum = 0
for line in sys.stdin:
    first = len(line)
    last = 0
    nums = []
    for m in re.finditer(nums_re, line):
        nums.append((m.start(), m.group(0)))

    nums.sort()
    first_word = nums[0][1]
    last_word = nums[-1][1]

    first_word = num_values.get(first_word, first_word)
    last_word = num_values.get(last_word, last_word)

    value = int(first_word + last_word)
    sum += value

print(sum)