133. Clone Graph (java)

Author: bluesword12350

solution/0133.Clone Graph/Solution.java

@@ -0,0 +1,15 @@
+class Solution {
+    private Map<Node, Node> cache;
+    public Node cloneGraph(Node node) {
+        cache = new HashMap<>(16);
+        return helper(node);
+    }
+    private Node helper(Node node) {
+        if (node == null) return null;
+        else if (cache.containsKey(node)) return cache.get(node);
+        Node nodeCopy = new Node(node.val,new ArrayList<>());
+        cache.put(node, nodeCopy);
+        for (Node neighbor : node.neighbors) nodeCopy.neighbors.add(helper(neighbor));
+        return nodeCopy;
+    }
+}