[1.2.1数据类型](1.2.1%E6%95%B0%E6%8D%AE%E7%B1%BB%E5%9E%8B.md) [1.2.2 go基础结构](1.2.2go%E5%9F%BA%E7%A1%80%E7%BB%93%E6%9E%84.md) [1.2.3 const及变量介绍](1.2.3const%E4%BB%8B%E7%BB%8D.md) [1.2.3os和time介绍](1.2.3os%E5%92%8Ctime%E4%BB%8B%E7%BB%8D.md) [1.2.4 字符串](1.2.4%E5%AD%97%E7%AC%A6%E4%B8%B2.md) [1.2.5条件判断](1.2.5%E6%9D%A1%E4%BB%B6%E5%88%A4%E6%96%AD.md) [1.2.6 homework](1.2.6homework.md)