Can I check include? at least one element in array with ruby on rails?? Here my example:
a = 1234
b = [1,5,6,7,8....]
if a.include?b[0] == true
app => return true
if a.include?b[0] == true and a.include?b[1] == false and a.include?b[2] == false and ......
app still return true
In the real app, I can't call b[0],b[1],b[2]... like that,So, how can I do to check include? at least one element in array, in rails app? Please help me :)
a1 = a.to_s.chars.map(&:to_i)
# => [1, 2, 3, 4]
b.any? {|i| a1.include?(i) }
# => true
UPDATE:
Ruby 2.4 has an Integer#digits. So you can do
a1 = a.digits
b.any? {|i| a1.include?(i) }
In cases like these, basic set algebra comes in handy. In your case, you want to check if the intersection of both sets (here implemented as arrays) is not empty, i.e. if they have any elements in common.
In Ruby, you can use the set operations for this:
a = "12345".chars.map(&:to_i)
b = [1,5,6,7,8]
intersection = a & b
has_common_elements = intersection.any?
You can read more about the intersection operator at the Ruby documentation. And while you are at that, you should also read about the union operator too, which complements the the intersection operator.
digits = a.to_s.chars.map(&:to_i)
(digits - b).empty?
bhas an element that == toaright ?