First array element that matches an element in another array

Question

I'm trying to return the first element in the given array that matches an element in a preset array. I have this:

def find_the_cheese(a)
  cheese_types = ["cheddar", "gouda", "camembert"]
  a.collect{|c| cheese_types.include?(c)}.include?(true)
end

But it returns true rather than the c value from the enclosed brackets. How can I return the matching element?

Veer3383 · Accepted Answer · 2015-12-19 20:17:55Z

2

Following code will returning elements from food which include in cheese_types

def find_the_cheese(food)
  cheese_types = ["cheddar", "gouda", "camembert"]
  food & cheese_types
end

Veer3383

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answered Dec 19, 2015 at 19:50

Vishal Zambre

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Comments

ndnenkov · Accepted Answer · 2015-12-19 18:32:17Z

1

The Array class includes the Enumerable module. Enumerable#find does just that:

def find_the_cheese(foods)
  cheeses = ["cheddar", "gouda", "camembert"]
  foods.find { |food| cheeses.include?(food) }
end

answered Dec 19, 2015 at 18:32

ndnenkov

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sawa · Accepted Answer · 2015-12-19 19:05:43Z

0

CheeseTypes = ["cheddar", "gouda", "camembert"]
def find_the_cheese(a)
  (a & CheeseTypes).first
end

answered Dec 19, 2015 at 19:05

sawa

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