[Ruby] .map // .select

# Array-Giving Enumerables

# map

# select

arr = ["a", "b", "c", "d"]

new_arr = arr.map { |ele| ele.upcase + "!" }

print new_arr
-----------------------------
#=>
["A!", "B!", "C!", "D!"]

num = [1,2,3,4,5,6]
new_num = num.select { |ele| ele % 2 == 0 }

print new_num
--------------------
#=>
[2, 4, 6]