Having problems adding to a array

array = [1,2,3,4,5] 
w = []
# Added my own is_number? method because 'gets.chomp' or just 'gets' method will always return a string
# with is_number? method we are checking if the characters inside the string are numbers
# if true then we will convert it to an integer and push it on the array

class String 
    def is_number?
      true if Float(self) rescue false
    end
end


def iterate(name) 
    if name.empty? || name.nil? 
        puts"Sorry there is nothing in array." 
    else 
        name.each { |o| print "#{o} \n" }
    end
end


def add_to_array(arg) 
    puts"Type in something to add in this array."
    name = gets.chomp

    if name.is_number?
        arg.push(name.to_i) 
        puts"added number" 
    else
        arg.push(name) 
        puts"Added string" 
    end 
end


def shifter(par)
    par.shift  
    puts"removed one"
    puts par

    # This loop will always run once so the user will be asked if they want to delete another
    # The loop will continue running and shifting the array until the user responds with 'NO' even if the array is empty
    loop do
        puts "Would you like to remove another?(YES?NO)" 
        h = gets.chomp 
        if h == "NO" 
            break 
        else 
            par.shift
        end
    end
end

iterate(array) 
iterate(w)

add_to_array(w)

puts"add another"

add_to_array(w) 
puts print w

add_to_array(w)

print w

shifter(w)

print w