JZ61-序列化二叉树
序列化二叉树
https://www.nowcoder.com/questionTerminal/cf7e25aa97c04cc1a68c8f040e71fb84?answerType=1&f=discussion
public class Solution {
String Serialize(TreeNode root) {
if(root==null){
return "";
}
Queue<TreeNode> queue = new LinkedList<TreeNode>();
StringBuilder sb = new StringBuilder();
queue.add(root);
while(!queue.isEmpty()){
TreeNode temp = queue.poll();
if(temp!=null){
sb.append(temp.val+",");
queue.add(temp.left);
queue.add(temp.right);
}else{
sb.append("#,"); //等于null也要添加入队列
}
}
return sb.toString();
}
TreeNode Deserialize(String data) {
if (data=="") {
return null;
}
String[] val = data.substring(0, data.length() - 1).split(",");
Queue<TreeNode> queue = new LinkedList<TreeNode>();
TreeNode root = new TreeNode(Integer.parseInt(val[0]));
int cur = 1;
queue.offer(root);
while (!queue.isEmpty()) {
TreeNode curNode = queue.poll();
if (!"#".equals(val[cur])){
curNode.left = new TreeNode(Integer.valueOf(val[cur]));
queue.offer(curNode.left);
}
cur++;
if (!"#".equals(val[cur])) {
curNode.right = new TreeNode(Integer.valueOf(val[cur]));
queue.offer(curNode.right);
}
cur++;
}
return root;
}
} 
