Improve the consistency between code and comments in Kotlin (#1268)

* style(kotlin): Make code and comments consistent.

* style(kotlin): convert comment location.

* style(c): Add missing comment.

* style(kotlin): Remove redundant semicolon, parenthesis and brace

* style(kotlin): Put constants inside the function.

* style(kotlin): fix unnecessary indentation.

* style(swift): Add missing comment.

* style(kotlin): Add missing comment.

* style(kotlin): Remove redundant comment.

* style(kotlin): Add missing comment.

* Update linked_list.kt

* style(csharp,js,ts): Add missing comment.

* style(kotlin): Remove empty lines.

* Update list.cs

* Update list.js

* Update list.ts

* roll back to commit 1

* style(cs,js,ts): Add missing comment in docfile.

* style(kotlin): Use normal element swapping instead of scope functions.

codes/kotlin/chapter_computational_complexity/recursion.kt

@@ -26,6 +26,7 @@ fun forLoopRecur(n: Int): Int {
     var res = 0
     // 递: 递归调用
     for (i in n downTo 0) {
+        // 通过“入栈操作”模拟“递”
         stack.push(i)
     }
     // 归: 返回结果