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_hashing/simple_hash.kt

@@ -6,11 +6,10 @@
 
 package chapter_hashing
 
-const val MODULUS = 1000000007
-
 /* 加法哈希 */
 fun addHash(key: String): Int {
     var hash = 0L
+    val MODULUS = 1000000007
     for (c in key.toCharArray()) {
         hash = (hash + c.code) % MODULUS
     }
@@ -20,6 +19,7 @@ fun addHash(key: String): Int {
 /* 乘法哈希 */
 fun mulHash(key: String): Int {
     var hash = 0L
+    val MODULUS = 1000000007
     for (c in key.toCharArray()) {
         hash = (31 * hash + c.code) % MODULUS
     }
@@ -29,6 +29,7 @@ fun mulHash(key: String): Int {
 /* 异或哈希 */
 fun xorHash(key: String): Int {
     var hash = 0
+    val MODULUS = 1000000007
     for (c in key.toCharArray()) {
         hash = hash xor c.code
     }
@@ -38,6 +39,7 @@ fun xorHash(key: String): Int {
 /* 旋转哈希 */
 fun rotHash(key: String): Int {
     var hash = 0L
+    val MODULUS = 1000000007
     for (c in key.toCharArray()) {
         hash = ((hash shl 4) xor (hash shr 28) xor c.code.toLong()) % MODULUS
     }