update: 203

Author: hijiangtao

README.md

@@ -113,6 +113,7 @@ This is the solutions collection of my LeetCode submissions, most of them are pr
 | 190 | [Reverse Bits](https://leetcode.com/problems/reverse-bits/)                                                                                     | [JavaScript](./src/reverse-bits/res.js)                                                                               | Easy       |
 | 196 | [Delete Duplicate Emails](https://leetcode.com/problems/delete-duplicate-emails/)                                                               | [SQL](./src/delete-duplicate-emails/res.txt)                                                                          | Easy       |
 | 197 | [Rising Temperature](https://leetcode.com/problems/rising-temperature/)                                                                         | [SQL](./src/rising-temperature/res.txt)                                                                               | Easy       |
+| 203 | [remove-linked-list-elements](https://leetcode.com/problems/remove-linked-list-elements/)                                                       | [TypeScript](./src/remove-linked-list-elements/res.ts)                                                                | Easy       |
 | 206 | [Reverse Linked List](https://leetcode.com/problems/reverse-linked-list/)                                                                       | [JavaScript](./src/reverse-linked-list/res.js)                                                                        | Easy       |
 | 207 | [Course Schedule](https://leetcode.com/problems/course-schedule/)                                                                               | [JavaScript](./src/course-schedule/res.js)                                                                            | Medium     |
 | 209 | [Minimum Size Subarray Sum](https://leetcode.com/problems/minimum-size-subarray-sum/)                                                           | [JavaScript](./src/minimum-size-subarray-sum/res.js)                                                                  | Medium     |

src/remove-linked-list-elements/res.ts

@@ -0,0 +1,42 @@
+/**
+ * Definition for singly-linked list.
+ * class ListNode {
+ *     val: number
+ *     next: ListNode | null
+ *     constructor(val?: number, next?: ListNode | null) {
+ *         this.val = (val===undefined ? 0 : val)
+ *         this.next = (next===undefined ? null : next)
+ *     }
+ * }
+ */
+
+/**
+ * 递归迭代均可，此法为迭代
+ * @param head
+ * @param val
+ */
+function removeElements(head: ListNode | null, val: number): ListNode | null {
+    let result = head;
+    let prevPointer = null;
+    let currentPointer = head;
+
+    if (!currentPointer) {
+        return result?.val === val ? null : head;
+    }
+
+    while (currentPointer) {
+        if (currentPointer.val === val) {
+            if (prevPointer) {
+                prevPointer.next = currentPointer.next;
+            }  else {
+                result = currentPointer.next;
+            }
+        } else {
+            prevPointer = currentPointer;
+        }
+
+        currentPointer = currentPointer.next;
+    }
+
+    return result;
+};