[4.1.if else语句](4.1.ifelse%E8%AF%AD%E5%8F%A5.md) [4.2.三元操作符](4.2.%E4%B8%89%E5%85%83%E6%93%8D%E4%BD%9C%E7%AC%A6.md) [4.3.switch语句](4.3.switch%E8%AF%AD%E5%8F%A5.md) [4.4.while循环](4.4.while%E5%BE%AA%E7%8E%AF.md) [4.5.do-while循环](4.5.do-while%E5%BE%AA%E7%8E%AF.md) [4.6.for循环](4.6.for%E5%BE%AA%E7%8E%AF.md) [4.7.考试题目举例](4.7.%E8%80%83%E8%AF%95%E9%A2%98%E7%9B%AE%E4%B8%BE%E4%BE%8B.md)