Merge pull request neetcode-gh#12 from anthonysim/asim/mergeklists

Added JS 23-Merge-K-Sorted-Lists

Author: neetcode-gh

javascript/23-Merge-K-Sorted-Lists.js

@@ -0,0 +1,29 @@
+var merge = function (l1, l2) {
+  let tempNode = new ListNode(0);
+  let current = tempNode;
+
+  while (l1 && l2) {
+    if (l1.val < l2.val) {
+      current.next = l1;
+      l1 = l1.next;
+    } else {
+      current.next = l2;
+      l2 = l2.next;
+    }
+    current = current.next;
+  }
+  if (l1) current.next = l1;
+  if (l2) current.next = l2;
+
+  return tempNode.next;
+}
+
+
+var mergeKLists = function (lists) {
+  let root = lists[0];
+
+  for (let i = 1; i < lists.length; i++) {
+    root = merge(root, lists[i]);
+  }
+  return root || null;
+};