链表的头文件以及一些简单的应用

最近软基的作业中，链表十分常用。于是将链表的声明和一些常用的功能封装到头文件里，以后直接引用就可以了。一下是链表的头文件：

list.h：

/************************************************************ * list.h                                                   * * To implement the list.                                   * * by Eric Brown.                                           * ************************************************************/#ifndef LIST_H#define LIST_Htypedef struct node_type{    int data;    struct node_type *next;}nodetype;typedef struct list_type{    nodetype *head;    int length;}listtype;/*list_init: to create a list.*/listtype * list_create(void);/*list_print: to print a list.*/void list_print(listtype *list);/*list_insert: to insert a node in a list by its address.*/listtype * list_insert(listtype *list, int location, int data);/*list_delete: to delete a node by its value.*/int list_delete(listtype *list, int data);/*list_input: to input a list.*/listtype * list_input(listtype *list, int length);/*list_delete_node: delete a certain node.*/listtype * list_delete_node(listtype *list, nodetype *node);/*list_add: to add a node.*/nodetype * list_add(listtype *list, int data);#endif

list.c：

/************************************************************ * list.c                                                   * * by Eric Brown.                                           * ************************************************************/#include "list.h"#include <stdio.h>#include <stdbool.h>#include <stdlib.h>/*node_insert: to insert a node behind the node.*/nodetype * node_insert(nodetype *node, int data);/*node_delete: to delete a node from the list.*/nodetype * node_delete(nodetype *cur, nodetype *pre);void error(int err);listtype * list_create(void){    listtype *list;        list = (listtype *)malloc(sizeof(listtype));    if (list == NULL)        error(1);        list->length = 0;    list->head = NULL;    return list;}nodetype * node_insert(nodetype *node, int data){    nodetype *temp;        temp = (nodetype *)malloc(sizeof(nodetype));    if (temp == NULL)        error(1);        temp->data = data;    temp->next = node->next;    node->next = temp;    return temp;}void list_print(listtype *list){    nodetype *temp;        if (list->length == 0 || list->head == NULL)    {        printf("This is an empty list!\n");        return ;    }        temp = list->head;    while (temp != NULL)    {        printf("%d\t", temp->data);        temp = temp->next;    }    printf("\n\n");}listtype * list_input(listtype *list, int num){    int temp;    nodetype *cur, *next;        if (num <= 0)        error(2);        cur = list->head;    if (cur == NULL)    {        scanf("%d", &temp);        cur = (nodetype *)malloc(sizeof(nodetype));        cur->data = temp;        num--;        list->length = 1;        list->head = cur;    } else{        while (cur->next != NULL)            cur = cur->next;    }    while (num--)    {        scanf("%d", &temp);        next = (nodetype *)malloc(sizeof(nodetype));        next->data = temp;        cur->next = next;        cur = next;        list->length++;    }    cur->next = NULL;    return list;}listtype * list_insert(listtype *list, int location, int data){    nodetype *temp, *cur;        cur = list->head;    if (location > 0 && location <= list->length)    {        while(--location)            cur = cur->next;                    node_insert(cur, data);    }     else if(location == 0)    {        temp = (nodetype *)malloc(sizeof(nodetype));        temp->data = data;        temp->next = list->head;        list->head = temp;    }    else     {        error(3);    }        list->length++;        return list;}nodetype * node_delete(nodetype *cur, nodetype *pre){    pre->next = cur->next;    free(cur);    return pre;}int list_delete(listtype *list, int data){    nodetype *cur, *pre;        for (cur = list->head, pre = NULL;          cur->data != data && cur != NULL;         pre = cur, cur = cur->next)        ;        if (cur == NULL)    {        printf("Can't find the data!\n");        return 0;    }    else if(cur != list->head)    {        node_delete(cur, pre);    }    else if(cur == list->head)     {        list->head = cur->next;        free(cur);    }        list->length--;    return data;}listtype * list_delete_node(listtype *list, nodetype *node){    nodetype *pre;        if (node == list->head)    {        list->head = node->next;        free(node);        list->length--;    }    else     {        pre = list->head;        while(pre->next != node)            pre = pre->next;                    node_delete(node, pre);    }    return list;}nodetype * list_add(listtype *list, int data){    nodetype *cur, *temp;        for (cur = list->head;          cur != NULL && cur->next != NULL;          cur = cur->next)        ;        temp = (nodetype *)malloc(sizeof(nodetype));    temp->data = data;    temp->next = NULL;    if (list->length == 0)        list->head = temp;    else        cur->next = temp;        list->length++;    return temp;}    void error(int err){    switch(err)    {        case 1:            printf("RAM error!\n");            break;        case 2:            printf("Length error!\n");            break;        case 3:            printf("Location error!\n");            break;        default:            printf("Unknown error!\n");    }    exit(EXIT_FAILURE);}

以下是一些功能的测试：

test.c：

#include <stdio.h>#include "list.h"int main(void){    listtype *list;    int length, location, data;        list = list_create();        for (;;)    {        printf("Please input the length of the list:");        scanf("%d", &length);                if (length <= 0)            break;                    list_input(list, length);        list_print(list);    }        for (;;)    {        printf("Please input the data you want to insert:");        scanf("%d", &data);        printf("The location:");        scanf("%d", &location);        if (location < 0)            break;        list_insert(list, location, data);        list_print(list);    }        for(;;)    {        printf("Please input the data you want to delete:");        scanf("%d", &data);        if(data == 0)            break;        list_delete(list, data);        list_print(list);    }        return 0;}

以下是运行结果：

以下是两个乱序链表应用归并排序的程序：

order.c：

#include "list.h"#include <stdio.h>#include <stdlib.h>/*find_min: to find the min num of the list.*/nodetype * find_min(listtype *list);/*order: to order two lists.*/listtype * order(listtype *listA, listtype *listB);int main(void){    listtype *listA, *listB, *result;    nodetype *node;    int lengthA, lengthB;        listA = list_create();    listB = list_create();        printf("listA:\n");    printf("length:");    scanf("%d", &lengthA);    list_input(listA, lengthA);        printf("listB:\n");    printf("length:");    scanf("%d", &lengthB);        list_input(listB, lengthB);        result = order(listA, listB);        list_print(result);        return 0;}nodetype * find_min(listtype *list){    nodetype *cur, *min;    cur = min = list->head;        while (cur != NULL)    {        if (cur->data < min->data)            min = cur;        cur = cur->next;    }        return min;}listtype * order(listtype *listA, listtype *listB){    nodetype *nodeA, *nodeB, *tail, *temp;    listtype *result;        result = list_create();        nodeA = find_min(listA);    nodeB = find_min(listB);    do    {        if (nodeA->data < nodeB->data)        {            list_add(result, nodeA->data);            list_delete_node(listA, nodeA);        }        else         {            list_add(result, nodeB->data);            list_delete_node(listB, nodeB);        }        nodeA = find_min(listA);        nodeB = find_min(listB);    }while(nodeA != NULL && nodeB != NULL);               for (tail = result->head; tail->next != NULL; tail = tail->next)        ;    if (nodeA == NULL)        while (nodeB != NULL)        {            temp = (nodetype *)malloc(sizeof(nodetype));            temp->data = nodeB->data;            tail->next = temp;            tail = temp;            list_delete_node(listB, nodeB);            nodeB =find_min(listB);        }            if (nodeB == NULL)        while (nodeA != NULL)        {            temp = (nodetype *)malloc(sizeof(nodetype));            temp->data = nodeA->data;            tail->next = temp;            tail = temp;            list_delete_node(listA, nodeA);            nodeA =find_min(listA);        }            tail->next = NULL;    return result;}   

以下是运行结果：