1 exercism fetch cpp crypto-square

# Crypto Square

Implement the classic method for composing secret messages called a square code.

Given an English text, output the encoded version of that text.

First, the input is normalized: the spaces and punctuation are removed from the English text and the message is downcased.

Then, the normalized characters are broken into rows. These rows can be regarded as forming a rectangle when printed with intervening newlines.

For example, the sentence

If man was meant to stay on the ground, god would have given us roots.

is normalized to:

ifmanwasmeanttostayonthegroundgodwouldhavegivenusroots

The plaintext should be organized in to a rectangle. The size of the rectangle (r x c) should be decided by the length of the message, such that c >= r and c - r <= 1, where c is the number of columns and r is the number of rows.

Our normalized text is 54 characters long, dictating a rectangle with c = 8 and r = 7:

 1 2 3 4 5 6 7 ifmanwas meanttos tayonthe groundgo dwouldha vegivenu sroots

The coded message is obtained by reading down the columns going left to right.

The message above is coded as:

 1 imtgdvsfearwermayoogoanouuiontnnlvtwttddesaohghnsseoau

Output the encoded text in chunks. Phrases that fill perfect rectangles (r X c) should be output c chunks of r length, separated by spaces. Phrases that do not fill perfect rectangles will have n empty spaces. Those spaces should be distributed evenly, added to the end of the last n chunks.

 1 imtgdvs fearwer mayoogo anouuio ntnnlvt wttddes aohghn sseoau

Notice that were we to stack these, we could visually decode the cyphertext back in to the original message:

 1 2 3 4 5 6 7 8 imtgdvs fearwer mayoogo anouuio ntnnlvt wttddes aohghn sseoau

## Getting Started

Make sure you have read the C++ page on exercism.io. This covers the basic information on setting up the development environment expected by the exercises.

## Passing the Tests

Get the first test compiling, linking and passing by following the three rules of test-driven development. Create just enough structure by declaring namespaces, functions, classes, etc., to satisfy any compiler errors and get the test to fail. Then write just enough code to get the test to pass. Once you've done that, uncomment the next test by moving the following line past the next test.

 1 #if defined(EXERCISM_RUN_ALL_TESTS)

This may result in compile errors as new constructs may be invoked that you haven't yet declared or defined. Again, fix the compile errors minimally to get a failing test, then change the code minimally to pass the test, refactor your implementation for readability and expressiveness and then go on to the next test.

Try to use standard C++11 facilities in preference to writing your own low-level algorithms or facilities by hand. CppReference is a wiki reference to the C++ language and standard library. If you are new to C++, but have programmed in C, beware of C traps and pitfalls.

## Source

J Dalbey's Programming Practice problems http://users.csc.calpoly.edu/~jdalbey/103/Projects/ProgrammingPractice.html

## Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.