Fixed compile warnings.

Author: javadev

src/main/kotlin/g0001_0100/s0021_merge_two_sorted_lists/Solution.kt

@@ -6,10 +6,19 @@ package g0001_0100.s0021_merge_two_sorted_lists
 
 import com_github_leetcode.ListNode
 
+/*
+ * Example:
+ * var li = ListNode(5)
+ * var v = li.`val`
+ * Definition for singly-linked list.
+ * class ListNode(var `val`: Int) {
+ *     var next: ListNode? = null
+ * }
+ */
 class Solution {
-    fun mergeTwoLists(l1: ListNode?, l2: ListNode?): ListNode? {
-        var l1 = l1
-        var l2 = l2
+    fun mergeTwoLists(list1: ListNode?, list2: ListNode?): ListNode? {
+        var l1 = list1
+        var l2 = list2
         var list: ListNode? = ListNode(-1)
         val head = list
         while (l1 != null || l2 != null) {

src/main/kotlin/g0001_0100/s0023_merge_k_sorted_lists/Solution.kt

@@ -7,7 +7,7 @@ import com_github_leetcode.ListNode
 
 class Solution {
     fun mergeKLists(lists: Array<ListNode>): ListNode? {
-        return if (lists.size == 0) {
+        return if (lists.isEmpty()) {
             null
         } else mergeKLists(lists, 0, lists.size)
     }
@@ -23,9 +23,9 @@ class Solution {
         }
     }
 
-    private fun mergeTwoLists(left: ListNode?, right: ListNode?): ListNode? {
-        var left = left
-        var right = right
+    private fun mergeTwoLists(leftLocal: ListNode?, rightLocal: ListNode?): ListNode? {
+        var left = leftLocal
+        var right = rightLocal
         if (left == null) {
             return right
         }

src/main/kotlin/g0001_0100/s0024_swap_nodes_in_pairs/Solution.kt

@@ -14,8 +14,8 @@ class Solution {
         return reverse(head, len)
     }
 
-    private fun getLength(curr: ListNode): Int {
-        var curr: ListNode? = curr
+    private fun getLength(currLocal: ListNode): Int {
+        var curr: ListNode? = currLocal
         var cnt = 0
         while (curr != null) {
             cnt++