第一个例子: 1 ... 5000的加法运算 1 sum = 0 2 i = 1 3 while true 4 sum += i 5 i += 1 6 break if i == 5001 7 end 8 9 sum = 0 10 (1..5000).each{|i| 11 sum += i 12 } 13 puts sum 第二个例子: 对 零 做除数这种情况进行简单的异常处理 1 a = 100 2 3 while true 4 b = gets.to_i 5 begin 6 puts a/…
出现问题: C:\Users\len>gem install rails ERROR: While executing gem ... (Gem::RemoteFetcher::FetchError) Errno::ETIMEDOUT: A connection attempt failed because the connected party di d not properly respond after a period of time, or established connection…
1.什么是类 2.类与实例的区别 3.自定义简单的类 生活中的垃圾分类,是集合上的概念 比如数学上的 1 a 2 b c 4 5分类为数字1 2 4 5 ,字母 a b c irb(main)::> "abc".class => String irb(main)::> String => String irb(main)::> String.class => Class irb(main)::> Class.class =…