colors = ["红色","绿色"]
puts colors.size

colors[5] = "黑色"
p colors
p colors[-8]

newbook = "红楼梦"
books1 = %w(西游记 红楼梦 三国演义 #{newbook})
books2 = %W(西游记 红楼梦 三国演义 #{newbook})
p books1
p books2
books2.unshift("隋唐演义")
p books2
books2.push("葫芦娃")
p books2
books2<<["海尔兄弟","极限挑战"]
p books2
books2[1,2]
p books2