feat: add typescript solution to lc problem:No.0142

No.0142.Linked List Cycle II

Author: zhaocchen

solution/0100-0199/0142.Linked List Cycle II/README.md

@@ -145,6 +145,41 @@ public class Solution {
 }
 ```
 
+### **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 detectCycle(head: ListNode | null): ListNode | null {
+    let slow = head, fast = head;
+    while (fast) {
+        slow = slow.next;
+        if (!fast.next) return null;
+        fast = fast.next.next;
+
+        if (fast == slow) {
+            let cur = head;
+            while (cur != slow) {
+                slow = slow.next;
+                cur = cur.next;
+            } 
+            return cur;
+        }
+    }
+    return null;
+};
+```
+
 ### **C++**
 
 ```cpp

solution/0100-0199/0142.Linked List Cycle II/README_EN.md

@@ -112,6 +112,41 @@ public class Solution {
 }
 ```
 
+### **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 detectCycle(head: ListNode | null): ListNode | null {
+    let slow = head, fast = head;
+    while (fast) {
+        slow = slow.next;
+        if (!fast.next) return null;
+        fast = fast.next.next;
+
+        if (fast == slow) {
+            let cur = head;
+            while (cur != slow) {
+                slow = slow.next;
+                cur = cur.next;
+            } 
+            return cur;
+        }
+    }
+    return null;
+};
+```
+
 ### **C++**
 
 ```cpp

solution/0100-0199/0142.Linked List Cycle II/Solution.ts

@@ -0,0 +1,30 @@
+/**
+ * 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 detectCycle(head: ListNode | null): ListNode | null {
+    let slow = head, fast = head;
+    while (fast) {
+        slow = slow.next;
+        if (!fast.next) return null;
+        fast = fast.next.next;
+
+        if (fast == slow) {
+            let cur = head;
+            while (cur != slow) {
+                slow = slow.next;
+                cur = cur.next;
+            } 
+            return cur;
+        }
+    }
+    return null;
+};