Merge Two Sorted Lists solution

Author: joshguha

20-mergeTwoSortedLists.js

@@ -0,0 +1,63 @@
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} l1
+ * @param {ListNode} l2
+ * @return {ListNode}
+ */
+var mergeTwoLists = function (l1, l2) {
+    if (l1 === null && l2 === null) {
+        return null;
+    } else if (l1 === null) {
+        return l2;
+    } else if (l2 === null) {
+        return l1;
+    }
+    let arr = [];
+    let i = l1;
+    let j = l2;
+    while (true) {
+        if (i.val < j.val) {
+            arr.push(i);
+            i = i.next;
+        } else {
+            arr.push(j);
+            j = j.next;
+        }
+
+        if (i === null) {
+            arr.push(j);
+            break;
+        } else if (j === null) {
+            arr.push(i);
+            break;
+        }
+    }
+
+    for (let i = 0; i < arr.length - 1; i++) {
+        arr[i].next = arr[i + 1];
+    }
+
+    return arr[0];
+};
+
+function ListNode(val, next) {
+    this.val = val === undefined ? 0 : val;
+    this.next = next === undefined ? null : next;
+}
+
+r = new ListNode(122);
+c = new ListNode(21, r);
+b = new ListNode(19, c);
+a = new ListNode(17, b);
+
+f = new ListNode(20);
+e = new ListNode(18, f);
+d = new ListNode(16, e);
+
+console.log(mergeTwoLists(a, d));