|
| 1 | +/** |
| 2 | + * Definition for a binary tree node. |
| 3 | + * public class TreeNode { |
| 4 | + * int val; |
| 5 | + * TreeNode left; |
| 6 | + * TreeNode right; |
| 7 | + * TreeNode(int x) { val = x; } |
| 8 | + * } |
| 9 | + */ |
| 10 | +publicclassCodec { |
| 11 | + |
| 12 | +privateinti; |
| 13 | + |
| 14 | +// Encodes a tree to a single string. |
| 15 | +publicStringserialize(TreeNoderoot) { |
| 16 | +List<String>list =newArrayList<>(); |
| 17 | +serializeDFS(root,list); |
| 18 | + |
| 19 | +returnString.join(",",list); |
| 20 | + } |
| 21 | + |
| 22 | +privatevoidserializeDFS(TreeNoderoot,List<String>list) { |
| 23 | +if (root ==null) { |
| 24 | +list.add("N"); |
| 25 | +return; |
| 26 | + } |
| 27 | +list.add(String.valueOf(root.val)); |
| 28 | +serializeDFS(root.left,list); |
| 29 | +serializeDFS(root.right,list); |
| 30 | + } |
| 31 | + |
| 32 | +// Decodes your encoded data to tree. |
| 33 | +publicTreeNodedeserialize(Stringdata) { |
| 34 | +String[]tokens =data.split(","); |
| 35 | +returndeserializeDFS(tokens); |
| 36 | + } |
| 37 | + |
| 38 | +privateTreeNodedeserializeDFS(String[]tokens) { |
| 39 | +Stringtoken =tokens[this.i]; |
| 40 | +if (token.equals("N")) { |
| 41 | +this.i++; |
| 42 | +returnnull; |
| 43 | + } |
| 44 | +varnode =newTreeNode(Integer.parseInt(token)); |
| 45 | +this.i++; |
| 46 | +node.left =deserializeDFS(tokens); |
| 47 | +node.right =deserializeDFS(tokens); |
| 48 | +returnnode; |
| 49 | + } |
| 50 | +} |
| 51 | + |
| 52 | +// Your Codec object will be instantiated and called as such: |
| 53 | +// Codec ser = new Codec(); |
| 54 | +// Codec deser = new Codec(); |
| 55 | +// TreeNode ans = deser.deserialize(ser.serialize(root)); |