下船类似的问题（用链表实现）

13个人围成一圈，从第一个人开始顺序报号，1，2，3，报到3者退出圈子，找出最后留在圈子中的人原来的序号，要求用链表实现

#include
#define NUM 13
struct peo
{
	int num;
	struct peo* next;
};
int main()
{
	struct peo arr[NUM] = { 0 };
	//建立环状链表
	struct peo* head = arr;
	for (int i = 0; i < NUM; i++)
	{
		head->num = i + 1;
		head->next = &arr[i + 1];
		head = head->next;
	}
	arr[NUM - 1].next = arr;
	int count = NUM;
	int j = 1;
	head = arr;
	while (count > 1)
	{
		//判断是否已经退出
		if (head->num == 0)
		{
			head = head->next;
			continue;
		}
		if (j == 3)
		{
			printf("第%d个人退出\n",head->num);
			head->num = 0;
			count--;
		}
		j++;
		head = head->next;
		if (j > 3)
		{
			j = 1;
		}
	}
	while (head->num == 0)
	{
		head = head->next;
		if (head->num != 0)
			printf("没有退出的人是:%d\n",head->num);
	}
	return 0;
}

输出结果：