feat: add typescript solution to lc problem: No.0203.Remove Linked List Elements (#437)

Author: zhaocchen

solution/0200-0299/0203.Remove Linked List Elements/README.md

@@ -136,6 +136,35 @@ func removeElements(head *ListNode, val int) *ListNode {
 }
 ```
 
+### **TypeScript**
+
+```ts
+/**
+ * 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)
+ *     }
+ * }
+ */
+
+ function removeElements(head: ListNode | null, val: number): ListNode | null {
+    let dummy: ListNode = new ListNode(0, head);
+    let cur: ListNode = dummy;
+    while (cur.next != null) {
+        if (cur.next.val == val) {
+            cur.next = cur.next.next;
+        } else {
+            cur = cur.next;
+        }
+    }
+    return dummy.next;
+};
+```
+
 ### **...**
 
 ```

solution/0200-0299/0203.Remove Linked List Elements/README_EN.md

@@ -127,6 +127,35 @@ func removeElements(head *ListNode, val int) *ListNode {
 }
 ```
 
+### **TypeScript**
+
+```ts
+/**
+ * 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)
+ *     }
+ * }
+ */
+
+ function removeElements(head: ListNode | null, val: number): ListNode | null {
+    let dummy: ListNode = new ListNode(0, head);
+    let cur: ListNode = dummy;
+    while (cur.next != null) {
+        if (cur.next.val == val) {
+            cur.next = cur.next.next;
+        } else {
+            cur = cur.next;
+        }
+    }
+    return dummy.next;
+};
+```
+
 ### **...**
 
 ```

solution/0200-0299/0203.Remove Linked List Elements/Solution.ts

@@ -0,0 +1,24 @@
+/**
+ * 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)
+ *     }
+ * }
+ */
+
+ function removeElements(head: ListNode | null, val: number): ListNode | null {
+    let dummy: ListNode = new ListNode(0, head);
+    let cur: ListNode = dummy;
+    while (cur.next != null) {
+        if (cur.next.val == val) {
+            cur.next = cur.next.next;
+        } else {
+            cur = cur.next;
+        }
+    }
+    return dummy.next;
+};