Some solutions for the julia path

julia/cars-assemble/README.md

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+# Cars Assemble
+
+Welcome to Cars Assemble 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
+
+## Comparison operators
+
+Comparison operators in Julia are similar to many other languages, though with some extra options for math-lovers.
+
+For equality, the operators are `==` (equal) and `!=` or `≠` (not equal).
+
+```julia
+txt = "abc"
+txt == "abc"  # true
+txt != "abc"  # false
+txt ≠ "abc"  # false (synonym for !=)
+```
+
+In addition, we have the various greater/less than operators.
+
+```julia
+1 < 3  # true
+3 > 3  # false
+3 <= 3  # true
+3 ≤ 3  # true (synonym for <=)
+4 >= 3  # true
+4 ≥ 3  # true (synonym for >=)
+```
+
+As often with Julia, an appropriate editor makes use of the mathematical symbol easy.
+Type `\ne`, `\le` or `\ge` then `TAB` to get `≠`, `≤` or `≥`.
+
+The previous example uses only numbers, but we will see in other parts of the syllabus that various additional types have a sense of ordering and can be tested for greater/less than.
+
+Comparison operators can be chained, which allows a clear and concise syntax:
+
+```julia
+n = 3
+1 ≤ n ≤ 5  # true (n "between" two limits)
+```
+
+The previous example is a synonym for `1 ≤ n && n ≤ 5`.
+
+## Branching with `if`
+
+This is the full form of an `if` statement:
+
+```julia
+if conditional1
+    statements...
+elseif conditional2
+    statements...
+else
+    statements...
+end
+```
+
+There is no need for parentheses `()` or braces `{}`, and indentation is "only" to improve readability _(but readability is very important!)_.
+
+Both `elseif` and `else` are optional, and there can be multiple `elseif` blocks.
+However, the `end` is required.
+
+It is possible to nest `if` statements, though you might want to help readability with the thoughtful use of parentheses, indents and comments.
+
+The shortest form of an `if` statement would be something like this:
+
+```julia
+if n < 0
+    n = 0
+end
+```
+
+As a reminder: only expressions that evaluate to `true` or `false` can be used as conditionals.
+Julia deliberately avoids any concept of "truthiness", so zero values, empty strings and empty arrays are _not_ equivalent to `false`. 
+
+## Ternary operator
+
+A simple and common situation is picking one of two values based on a conditional.
+
+Julia, like many languages, has a ternary operator to make this more concise.
+
+The syntax is `conditional ? value_if_true : value_if_false`.
+
+So the previous example could be rewritten:
+
+```julia
+n = n < 0 ? 0 : n
+```
+
+Parentheses are not required by the compiler, but may improve readability.
+
+## Instructions
+
+In this exercise you will be writing code to analyze the production of an assembly line in a car factory. 
+The assembly line's speed can range from `0` (off) to `10` (maximum).
+
+At its lowest speed (`1`), `221` cars are produced each hour. 
+The production increases linearly with the speed. 
+So with the speed set to `4`, it should produce `4 * 221 = 884` cars per hour. 
+However, higher speeds increase the likelihood that faulty cars are produced, which then have to be discarded. 
+
+You have three tasks.
+Each of the required functions takes a single integer parameter, the speed of the assembly line.
+
+## 1. Calculate the success rate
+
+Implement the `success_rate()` method to calculate the probability of an item being created without error for a given speed. 
+The following table shows how speed influences the success rate:
+
+- `0`: 0% success rate.
+- `1` to `4`: 100% success rate.
+- `5` to `8`: 90% success rate.
+- `9`: 80% success rate.
+- `10`: 77% success rate.
+
+```julia-repl
+julia> success_rate(10)
+0.77
+```
+
+## 2. Calculate the production rate per hour
+
+Implement the `production_rate_per_hour()` method to calculate the assembly line's production rate per hour, taking into account its success rate.
+
+```julia-repl
+julia> production_rate_per_hour(6)
+1193.4
+```
+
+Note that the value returned is floating-point.
+
+## 3. Calculate the number of working items produced per minute
+
+Implement the `working_items_per_minute()` method to calculate how many working cars are produced per minute:
+
+```julia-repl
+julia> working_items_per_minute(6)
+19
+```
+
+Note that the value returned is an integer: incomplete items are not included.
+
+## Source
+
+### Created by
+
+- @colinleach