一种多叉树的例子

#include "stdio.h"
#include "stdlib.h"

#define new(Class) (Class*)malloc(sizeof(Class))  

typedef struct node Node;
struct node{
	Node *next; 
	Node *nextLayer;  //有地址的话代表有下一层链表 	
	int num;
};

//弄一个4层的多叉例子树 
Node* createTree(){ 
	//声明 
	Node* head;
	Node* layer2;
	Node* layer3_1;
	Node* layer3_2;
	//构造第一层（根） 
	head =  new(Node);
	head->num = 1;
	head->next = NULL;
	//构造第二层
	layer2 = new(Node);
	layer2->num = 2;
	layer2->next = new(Node);
	
	layer2->next->num = 3;
	layer2->next->nextLayer = NULL;
	layer2->next->next = new(Node);
	
	layer2->next->next->num = 4;
	layer2->next->next->next = NULL;
	head->nextLayer = layer2; //根结点(num为1的结点)和第二层(num为2的结点)连接起来
	//构造第三层_第一段 
	layer3_1 = new(Node);
	layer3_1->num = 5;
	layer3_1->nextLayer = NULL; 
	layer3_1->next = new(Node);
	
	layer3_1->next->num = 6;
	layer3_1->next->nextLayer = NULL;
	layer3_1->next->next = NULL;
	layer2->nextLayer = layer3_1; //第二层(num为2的结点)连接第三层_第一段(num为5的结点) 
	//构造第三层_第二段 
	layer3_2 = new(Node);
	layer3_2->num = 7;
	layer3_2->nextLayer = NULL; 
	layer3_2->next = new(Node);
	
	layer3_2->next->num = 8;
	layer3_2->next->nextLayer = NULL;
	layer3_2->next->next = new(Node);
	
	layer3_2->next->next->num = 9;
	layer3_2->next->next->nextLayer = NULL;
	layer3_2->next->next->next = new(Node);
	
	layer3_2->next->next->next->num = 10;
	layer3_2->next->next->next->nextLayer = NULL;
	layer3_2->next->next->next->next = NULL;
	layer2->next->next->nextLayer = layer3_2;  //第二层(num为4的结点)连接第三层_第二段(num为7的结点) 
	return head;
}

//先序读取 
void read(Node* head){
	Node* cursor = head;
	/**遍历每一个结点的数据，
	   遇到结点有下一层的直接调用本函数读当前结点的下一层，
	   下一层读完继续接着上次循环读下一个节点，建议画出递归流程理解 **/
	while(cursor != NULL) {
		printf("%d\n", cursor->num);
		if(cursor->nextLayer != NULL) {
			read(cursor->nextLayer);
		}
		cursor = cursor->next;
	}
}


int main(){
	read(createTree()); 
	return 0;
}