add: [week-8] clong-graph

Author: Yongseok-Choi-dev

clone-graph/Solution.java

@@ -0,0 +1,86 @@
+import java.util.HashMap;
+import java.util.Map;
+
+/*
+// Definition for a Node.
+class Node {
+    public int val;
+    public List<Node> neighbors;
+    public Node() {
+        val = 0;
+        neighbors = new ArrayList<Node>();
+    }
+    public Node(int _val) {
+        val = _val;
+        neighbors = new ArrayList<Node>();
+    }
+    public Node(int _val, ArrayList<Node> _neighbors) {
+        val = _val;
+        neighbors = _neighbors;
+    }
+}
+*/
+class Solution {
+    public Map<Node, Node> nMap = new HashMap<>();
+
+    public Node cloneGraph(Node node) {
+        if (node == null)
+            return null;
+
+        if (nMap.containsKey(node)) {
+            return nMap.get(node);
+        }
+
+        Node clone = new Node(node.val);
+        nMap.put(node, clone);
+
+        for (Node nei : node.neighbors) {
+            clone.neighbors.add(cloneGraph(nei));
+        }
+
+        return clone;
+    }
+}
+
+class WrongSolution {
+    public Node graph;
+    public Map<Node, Node> nMap = new HashMap<>();
+
+    public Node cloneGraph(Node node) {
+        if (node == null)
+            return null;
+
+        graph = new Node(node.val);
+        nMap.put(node, graph);
+
+        // print(graph);
+
+        return clone(node, graph);
+    }
+
+    public Node clone(Node node, Node cur) {
+        for (int i = 0; i < node.neighbors.size(); i++) {
+            Node adj = node.neighbors.get(i);
+
+            if (nMap.containsKey(adj)) {
+                return nMap.get(adj);
+            }
+
+            nMap.put(adj, new Node(adj.val));
+            cur.neighbors.add(nMap.get(adj));
+            clone(adj, nMap.get(adj));
+        }
+
+        return cur;
+    }
+
+    public void print(Node node) {
+        System.out.println("visit " + node.val);
+
+        for (int i = 0; i < node.neighbors.size(); i++) {
+            Node adj = node.neighbors.get(i);
+            System.out.println("nei " + adj.val);
+            print(adj);
+        }
+    }
+}