Alphametics

Write a function to solve alphametics puzzles.

Alphametics is a puzzle where letters in words are replaced with numbers.

For example SEND + MORE = MONEY:

  S E N D
  M O R E +
-----------
M O N E Y

Replacing these with valid numbers gives:

  9 5 6 7
  1 0 8 5 +
-----------
1 0 6 5 2

This is correct because every letter is replaced by a different number and the words, translated into numbers, then make a valid sum.

Each letter must represent a different digit, and the leading digit of a multi-digit number must not be zero.

Write a function to solve alphametics puzzles.

Hints

• To parse the text, you could try to use the Sprache library. You can also find a good tutorial here.
• You can solve this exercise with a brute force algorithm, but this will possibly have a poor runtime performance. Try to find a more sophisticated solution.
• Hint: You could try the column-wise addition algorithm that is usually taught in school.

Running the tests

To run the tests, run the command dotnet test from within the exercise directory.

Initially, only the first test will be enabled. This is to encourage you to solve the exercise one step at a time. Once you get the first test passing, remove the Skip property from the next test and work on getting that test passing. Once none of the tests are skipped and they are all passing, you can submit your solution using exercism submit Alphametics.cs

Further information

For more detailed information about the C# track, including how to get help if you're having trouble, please visit the exercism.io C# language page.