Ruby – How to get the first key and value pair from a hash table in Ruby

hashruby

I'm trying to get the first key and value key from a hash table in ruby. I don't know the key values of the hash because it is passed to the method. I cant find anywhere online how to find the first key/value as a separate hash table.
I think hash[0] will just try to find an element with a name 0 it just returns nil when I run the code.

I know I can find the key name and the value and then create a new hash from them but i wonder if there is an easier way to do this so I get a hash right away.

here is my code: 

def rps_game_winner(game)

rock_in_hash = game.invert['R']
paper_in_hash = game.invert['P']
scissors_in_hash = game.invert['S']

if(rock_in_hash)
      if(paper_in_hash)
        return paper_in_hash;
      elsif(scissors_in_hash)
        return rock_in_hash
      end
    elsif(paper_in_hash)
      if(rock_in_hash)
        return paper_in_hash
      elsif(scissors_in_hash)
        return scissors_in_hash
      end
    end
        key = game.keys[-1]
        value = game.values[-1]
            winner = {key => value}
    return winner 
    end

game_one = { "Bob" => 'P', "Jim" => 'P' }

puts rps_game_winner(game_one)

This gets me the correct result the problem is I don't understand why it's -1 instead of zero…
And i was hoping there was a better way to get the first key/value pair of a hash table instead of creating new hash table with the key and value you retrieved from the previous table.

Best Answer

You can just do

key, value = hash.first

or if you prefer:

key = hash.keys[0]
value = hash.values[0]

Then maybe:

new_hash = {key => value}
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