链表的简单操作

#include <iostream>
#include <stdio.h>
#include <string>

using namespace std;

typedef struct student
{
	int data;
	struct student *next;
}node;

node *create()
{
	node *head, *p, *s;
	int x, cycle = 1;
	head = (node *)malloc(sizeof(node));
	p = head;
	while (cycle)
	{
		printf("Please input the data:");
		scanf("%d", &x);
		if (x != 0)
		{
			s = (node *)malloc(sizeof(node));
			s->data = x;
			printf("%d\n", s->data);
			p->next = s;
			p = s;
		}
		else
			cycle = 0;
	}
	//head = head->next;
	p->next = NULL;
	return head;
}

int lenght(node *head)
{
	int i = 0;
	node *p;
	p = head;
	while(p != NULL)
	{
		p = p->next;
		i++;
	}
	return i;
}

void print(node *head)
{
	printf("The list data elements:\n");
	node *p;
	p = head;
	while (p != NULL)
	{
		if (p->next == NULL)
		{
			break;
		}
		p = p->next;
		printf("%d\n", p->data);
		
	}
	return;
}

node *deletes(node *head, int num)
{
	node *p1, *p2;
	p1 = head;
	while (num != p1->data && p1->next != NULL)
	{
		p2 = p1;
		p1 = p1->next;
	}

	if (num == p1->data)
	{
		if (p1 == head)
		{
			head = p1->next;
			free(p1);
		}
		else
			p2->next = p1->next;
	}
	else
		printf("%d could not been found", num);
	return head;
}

node *insert(node *head, int num)
{
	node *p0, *p1, *p2;
	p1 = head;
	p0 = (node *)malloc(sizeof(node));
	p0->data = num;
	//cout << p1->data;
	while (p0->data > p1->data && p1->next != NULL)
	{
		p2 = p1;
		p1 = p1->next;
	}
	if (p0->data <= p1->data)
	{
		if (head == p1)
		{
			p0->next = p1;
			head = p0;
		}
		else
		{
			p2->next = p0;
			p0->next = p1;
		}
	}
	else
	{
		p1->next = p0;
		p0->next = NULL;
	}
	return head;
}

node *sort(node *head)
{
	node *p, *p2, *p3;
	int n;
	int temp;
	n = lenght(head);
	if (head == NULL || head->next == NULL)
	{
		return head;
	}
	p = head;
	for (int j = 1; j < n; ++j)
	{
		p = head;
		for (int i = 0; i < n - j; ++i)
		{
			if (p->data > p->next->data)
			{
				temp = p->data;
				p->data = p->next->data;
				p->next->data = temp;
			}
			p = p->next;
		}
	}
	return head;
}

node *reverse(node *head)
{
	node *p1, *p2, *p3;
	if (head == NULL || head->next == NULL)
	{
		return head;
	}
	p1 = head;
	p2 = p1->next;
	while (p2)
	{
		p3 = p2->next;
		p2->next = p1;
		p1 = p2;
		p2 = p3;
	}

	head->next = NULL;
	head = p1;
	return head;
}

int main(int argc, char *argv[])
{
	node *head;
	int x;
	head = create();
	printf("Lenght of the list:%d", lenght(head));
	print(head);
	printf("Input the data that you want to delete from the list:");
	scanf("%d", &x);
	head = deletes(head, x);
	print(head);
	printf("Input the data that you want to insert to the list:");
	scanf("%d", &x);
	insert(head, x);
	print(head);
	return 0;
}