Class: ReduceDrill

Inherits:
Drill
  • Object
show all
Defined in:
lib/ruby_drills/array/reduce_drill.rb

Constant Summary

Constants included from Commands

Commands::GAMBLER

Instance Attribute Summary

Attributes inherited from Drill

#hints, #next, #previous

Instance Method Summary collapse

Methods inherited from Drill

#done?, #drills, #expected, #initialize, #non!

Methods included from Commands

#back, #clear, #continue, #fail, #fold, #help, #hint, #quit, #review, #skip, #welcome, #win

Constructor Details

This class inherits a constructor from Drill

Instance Method Details

#reference ⇒ Object 



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# File 'lib/ruby_drills/array/reduce_drill.rb', line 23

def reference
  "@values.reduce(:+)/@values.size"
end

#setup ⇒ Object 



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# File 'lib/ruby_drills/array/reduce_drill.rb', line 3

def setup
  @values = [3, 5, 19, 25, 23, 40, 55, 36, 32, 52]
  @hints = ["How could you reduce this problem to something simpler?",
            "TODO: Inject a hint here...",
            "This method is called foldLeft in some languages.",
            "http://ruby-doc.org/core-1.9.3/Enumerable.html#method-i-reduce"]
end

#show ⇒ Object 



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# File 'lib/ruby_drills/array/reduce_drill.rb', line 11

def show
  puts %{
@values = #{@values.inspect}

The mean of the numbers in @values is #{expected.inspect}.

Use a method that combines the items in an Enumerable by
iterating over them to calculate this mean.

}
end

#valid?(input) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ruby_drills/array/reduce_drill.rb', line 27

def valid?(input)
  ['reduce', 'inject'].any? {|x| input.include?(x) }
end