左孩子右兄弟表示多叉树查找返回下一个节点

struct node{      node *parent;      node *next;      node *child;  };    node* next(node *node){      if(node == null)          return null;      if(node->child != null)          return node->child;      if(node->next != null)          return node->next;     while(node->parent->next == NULL && node->parent != root)          node = node->parent;      return node->parent->next; }