From: Matthew Moss <matt@...>
Date: 2008-12-13T03:36:55+09:00
Subject: [QUIZ] Mix and Match (#186)

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## Mix and Match (#186)

I purchased a number of scented candles recently for sending out to  
friends and family. While I could be accused of being lazy by getting  
candles for several people, I'd like to mix up the candles a bit so  
that each recipient gets a different combination of scents.

Please help me out! Your task is to write a method that randomizes and  
mixes up the individual candles into groups, one per recipient, in  
order to minimize group duplication. So, for example:

     candles = { :orange   => 3,
                 :vanilla  => 2,
                 :lavender => 2,
                 :garden   => 4 }

     recipients = %w(janet nancy susan)

     candles_per_recipient = 3

     > mix_and_match(candles, recipients, candles_per_recipient)

     => { "janet" => [:garden, :lavender, :orange],
          "nancy" => [:garden, :orange, :vanilla],
          "susan" => [:garden, :lavender, :vanilla],
          :extra  => { :orange   => 1,
                       :vanilla  => 0,
                       :lavender => 0,
                       :garden   => 1
                     }
         }

If it is impossible to have a unique combination for every recipient,  
you should still generate some set of combinations, minimizing  
repetition of combinations.

If the number of recipients times the number of candles per recipient  
is more than the supply, generate an error.