[Ruby] Review about nesting of each


If it is an "array", it can be easily retrieved, but if it is an "array inside an array",

――I think a little ――I can't get the value I want

It is an article for those who say. I hope you find it helpful.

table of contents

--Practice --Problem --Answer (commentary) --Process

--Summary --References



Output the fruit name and total amount from the following array.


fruits_price = [["apple", [200, 300, 400]], ["banana", [100, 200, 300]], ["grape", [2000, 3000]]]

Answer (commentary)

Answer example

fruits_price.each do |fruit|
# fruits_Extract the array one by one from price and extract it with fruit(By using each, you can process the array in the array.)

  sum = fruit[1].sum
# fruit[1](Amountpart)sum(Totalamount)

  puts "#{fruit[0]}The total amount of#{sum}It's a yen"

Another solution

fruits_price.each do |fruits, prices|
  puts "#{fruits}The total amount of#{prices.sum}It's a yen"


** 1. Think about what you want to get **

--Fruit name --Total amount of each fruit

** 2. How to retrieve elements for arrays **

--Retrieve with each ――What number of them to get

** 3. How to get the total value **

--Output sum of elements with sum


--Think about what value you want to take --Isolate the problem and find out how to output it. --You can easily get the sum of elements with sum


-Ruby 3.0.0 Reference Manual (sum)

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