lichuang

'''
leetcode 117: https://leetcode.cn/problems/populating-next-right-pointers-in-each-node-ii/description/
给定一个二叉树：

struct Node {
  int val;
  Node *left;
  Node *right;
  Node *next;
}

lichuang

#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>

typedef unsigned char mystring_data_t;

typedef struct mystring {
  mystring_data_t * data;
  size_t size;
  size_t length;