# [Ruby] Find numbers in arrays

## A word

I've been busy for some reason recently ... I don't have a lot of work, but ... why Since the contract expires, I will move the office if I prepare to move. What timing

So the main subject The title is reminiscent of someone wearing red and white border clothes with glasses ...

## Find any number in the array

Challenge the tasks you did before in the morning study today (second time)

array=[1,3,5,6,9,10,13,20,26,31]

• Output example: Please enter the number you want to search 5 5 is the second in the array 7 7 does not exist in the array

Put it out like this I forgot a little and saw the explanation without understanding. A method of taking out the data in the middle, comparing the size on the left and right, narrowing the range by iterative processing, and finally guessing which number. The so-called binary search

So, I was ashamed to say that I learned the word "linear search" for the first time in the content I commented on yesterday's article, and I posted it with the intention of trying this method.

``````def linear_search(array, num)
array.each_with_index do |n, index|
if n == num
return index
end
end
return
end
array=[1,3,5,6,9,10,13,20,26,31]

puts "Please enter the number you want to search"
num = gets.to_i

result = linear_search(array, num)

if result.nil?
puts "#{num}Does not exist in the array"
else
puts "#{num}Is an array#{result+1}Exists second"
end

* The content pointed out in the comments has been corrected.

``````

Now you can get similar output results. I wasn't aware of words such as linear search, but it felt like I was doing it all the time, so it was easier for me personally.

Congratulations