feat(solution): add solution 0817 [Java]

Linked List Components

Author: yanglbme

README.md

@@ -101,6 +101,7 @@ Complete [solutions](https://github.com/doocs/leetcode/tree/master/solution) to
 | 0184 | [Department Highest Salary](https://github.com/doocs/leetcode/tree/master/solution/0184.Department%20Highest%20Salary) | `SQL` |
 | 0328 | [Odd Even Linked List](https://github.com/doocs/leetcode/tree/master/solution/0328.Odd%20Even%20Linked%20List) | `Linked List` |
 | 0343 | [Integer Break](https://github.com/doocs/leetcode/tree/master/solution/0343.Integer%20Break) | `Math`, `Dynamic Programming` |
+| 0817 | [Linked List Components](https://github.com/doocs/leetcode/tree/master/solution/0817.Linked%20List%20Components) | `Linked List` |
 | 0938 | [Range Sum of BST](https://github.com/doocs/leetcode/tree/master/solution/0938.Range%20Sum%20of%20BST) | `Binary Search Tree` |
 
 

solution/0817.Linked List Components/Solution.java

@@ -0,0 +1,38 @@
+/**
+ * Definition for singly-linked list.
+ * public class ListNode {
+ *     int val;
+ *     ListNode next;
+ *     ListNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    public int numComponents(ListNode head, int[] G) {
+        if (head == null || G == null) {
+            return 0;
+        }
+        Set<Integer> set = new HashSet<>();
+        for (int val : G) {
+            set.add(val);
+        }
+        int n = G.length;
+        ListNode cur = head;
+        int cnt = 0;
+        boolean flag = false;
+        while (cur != null) {
+            while (cur != null && set.contains(cur.val)) {
+                flag = true;
+                cur = cur.next;
+            }
+            if (flag) {
+                ++cnt;
+                flag = false;
+            }
+            
+            if (cur != null) {
+                cur = cur.next;
+            }
+        }
+        return cnt;
+    }
+}