https://blog.iletter.top/index.php/archives/42.html zh-CN 请实现一个函数，把字符串 s 中的每个空格替换成"%20"。示例 1：输入：s = "We are happy."输出："We%20are%20happy.&quo... Thu, 01 Jan 1970 08:00:00 +0800 Thu, 01 Jan 1970 08:00:00 +0800