7-segment digits can be represented in ASCII using _| characters. Here are the size 1 digits:
_ _ _ _ _ _ _ _ | _| _| |_| |_ |_ | |_| |_| | | | |_ _| | _| |_| | |_| _| |_|
Larger sizes are formed by making each segment proportionately longer. Here are a couple size 3 digits.
___ ___ ___ ___ ___ ___ ___ | | | | | | | | | | | | | | | | | | | | |___| |___ | |___ ___| | | |___| | | | | | | | | | | | | | | | | | | | | |___| |___| | ___| ___| |___| ___|
Goal
In this challenge, you are to write a program/function that can take a single digit as input and identify its size. The catch: if the input is not a valid digit, then your program should output 0.
This is code-golf, fewest bytes wins.
You can write either a program or a function, which can receive the digit either as STDIN or an argument, and print/return the value.
Digits will be provided as a multi-line string, padded with the minimal amount of trailing whitespace needed to make it a perfect rectangle. The trailing newline is an optional part of input. There will be no unneeded leading spaces.
When a non-digit is passed, it will still be comprised of _| characters, padded to a rectangle, and have no unneeded leading spaces. There will be no blank lines. You won't have to deal with empty input.
Output should be a single non-negative integer, with optional trailing newline. If the input is not a proper digit of any size, output 0. Else, output the size.
Here is a handy guide for the widths and heights of each digit for a given size N.
Digit Height Width (not counting newlines) 1 2N 1 2 2N+1 N+2 3 2N+1 N+1 4 2N N+2 5 2N+1 N+2 6 2N+1 N+2 7 2N+1 N+1 8 2N+1 N+2 9 2N+1 N+2 0 2N+1 N+2
I/O Examples
In:
__ | __| | __|
Out:
2
In:
| | |
Out:
0 //because it is of an invalid height. Either 1 char too short or tall.
In:
| | | | | | |____| | | | |
Out:
4
In:
___ | |___ | | |___|
Out:
0 //1 char too wide
In:
_ |_| | |
Out:
0 //it's not a digit
In:
__ | |__ | __|
Out:
2
In:
_ _ _| _| |_ _|
Out:
0 //both would be valid individually, but input should be a *single* digit
In:
_ |_| |_|
Out:
1
In:
| |
Out:
1
In:
__|_ | _ | _ |__
Out:
0
This is approximately the inverse of Transform number into 7-segment display pattern, from 3 years back.
