#!/usr/bin/env python
# 2023 - Advent Of Code 1

# file = 'input_example.txt'
file = 'input.txt'

with open(file, encoding="utf-8") as f:
    accum = 0
    for line in f.readlines():
        first_num = -1
        for c in line:
            if '0' <= c <= '9':
                if first_num == -1:
                    first_num = c
                last_num = c
        line_num = first_num + last_num
        # print(f"first: {first_num}, last: {last_num}")
        # print(f"line_num: {line_num}")
        accum += int(line_num)

print(f"sum: {accum}")