Some solutions for the julia path

julia/chessboard/README.md

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+# Chessboard
+
+Welcome to Chessboard on Exercism's Julia Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+If you get stuck on the exercise, check out `HINTS.md`, but try and solve it without using those first :)
+
+## Introduction
+
+Suppose you want all the non-negative integers up to 1000.
+It would be ridiculous if you had to type these into an array.
+
+For this we have the `range` type:
+
+```julia-repl
+julia> 0:1000
+0:1000
+
+julia> typeof(0:1000)
+UnitRange{Int64}
+```
+
+Ranges are very common: not just to save you typing, but also as return types from functions.
+
+Note that ranges are _not_ vectors.
+They are just a set of instructions to generate a sequence ("lazy" evaluation, or an "iterator").
+
+If you need a range as a vector, use the `collect()` function for conversion:
+
+```julia-repl
+julia> collect(0:5)
+6-element Vector{Int64}:
+ 0
+ 1
+ 2
+ 3
+ 4
+ 5
+```
+
+The step size can be specified, in this case 0.3:
+
+```julia-repl
+julia>  collect(1.0:0.3:2.0)
+4-element Vector{Float64}:
+ 1.0
+ 1.3
+ 1.6
+ 1.9
+```
+
+So the syntax is `start:stepsize:stop`.
+Both end limits are _inclusive_, as seen in the integer example.
+If the step size does not divide exactly into `stop - start`, the last element will avoid exceeding `stop`.
+
+## Letter ranges
+
+Non-numeric sequences can also be used in ranges.
+The simplest example is ASCII letters:
+
+```julia-repl
+julia> 'a':'d'
+'a':1:'d'
+
+julia> typeof('a':'d')
+StepRange{Char, Int64}
+
+julia> collect('a':'d')
+4-element Vector{Char}:
+ 'a': ASCII/Unicode U+0061 (category Ll: Letter, lowercase)
+ 'b': ASCII/Unicode U+0062 (category Ll: Letter, lowercase)
+ 'c': ASCII/Unicode U+0063 (category Ll: Letter, lowercase)
+ 'd': ASCII/Unicode U+0064 (category Ll: Letter, lowercase)
+```
+
+The `Char` type will be covered in more detail in another Concept.
+For now, just treat these as single characters in single-quotes.
+
+## Functions and operators for ranges
+
+Check the limits of a range with `first()` and `last()`.
+
+```julia
+ r = 1:10  # => 1:10
+ first(r)  # => 1
+ last(r)   # => 10
+```
+
+## More on vector indexing
+
+Integer ranges and vectors can be used in vector indexing:
+
+```julia
+nums = collect(10.0:50.0)
+nums[3:2:7]  # gives [12.0, 14.0, 16.0]
+nums[ [3, 5, 7] ] # also gives [12.0, 14.0, 16.0]
+```
+
+## Instructions
+
+As a chess enthusiast, you would like to write your own version of the game. Yes, there maybe plenty of implementations of chess available online already, but yours will be unique!
+
+But before you can let your imagination run wild, you need to take care of the basics. Let's start by generating the board.
+
+Each square of the chessboard is identified by a letter-number pair. The vertical columns of squares, called files, are labeled A through H. The horizontal rows of squares, called ranks, are numbered 1 to 8.
+
+## 1. Define the rank range
+
+Implement the `rank_range()` function. It should return a range of integers, from 1 to 8.
+
+```julia-repl
+julia> rank_range()
+# output omitted
+```
+
+## 2. Define the file range
+
+Implement the `file_range()` function. 
+It should return a range of integers, from the uppercase letter A, to the uppercase letter H.
+
+```julia-repl
+julia> file_range()
+# output omitted
+```
+
+## 3. Transform the rank range into a vector of ranks
+
+Implement the `ranks()` function. It should return a vector of integers, from 1 to 8. 
+Do not write the vector by hand, generate it from the range returned by the `rank_range()` function.
+
+```julia-repl
+julia> ranks()
+[1, 2, 3, 4, 5, 6, 7, 8]
+```
+
+## 4. Transform the file range into a vector of files
+
+Implement the `files` function. It should return a vector of characters, from 'A' to 'H'. 
+Do not write the vector by hand, generate it from the range returned by the `file_range()` function.
+
+```julia-repl
+julia> files()
+['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H']
+```
+
+## Source
+
+### Created by
+
+- @colinleach