What is the sum of all of the calibration values?
Your puzzle answer was 54450.
## Part Two
Your calculation isn't quite right. It looks like some of the digits are actually spelled out with letters: `one`, `two`, `three`, `four`, `five`, `six`, `seven`, `eight`, and `nine` also count as valid "digits".
Equipped with this new information, you now need to find the real first and last digit on each line. For example:
```
two1nine
eightwothree
abcone2threexyz
xtwone3four
4nineeightseven2
zoneight234
7pqrstsixteen
```
In this example, the calibration values are `29`, `83`, `13`, `24`, `42`, `14`, and `76`. Adding these together produces `281`.