输入若干行文本以“END!”结尾，根据输入文本生成邻接表，使用邻接表构成图来表达地铁线路C语言

以下是一个简单的实现：

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

#define MAX_STATION_NAME 50

typedef struct station Station;
struct station {
    char name[MAX_STATION_NAME];
    Station *next;
};

typedef struct {
    Station *head;
} AdjList;

typedef struct {
    int num_stations;
    AdjList *adj_lists;
} Subway;

void add_station(AdjList *adj_list, char *name) {
    Station *new_station = (Station*) malloc(sizeof(Station));
    strcpy(new_station->name, name);
    new_station->next = adj_list->head;
    adj_list->head = new_station;
}

void add_connection(AdjList *adj_list, char *station1, char *station2) {
    Station *station = adj_list->head;
    while (station != NULL && strcmp(station->name, station1) != 0) {
        station = station->next;
    }
    if (station == NULL) {
        printf("Error: station %s does not exist\n", station1);
        return;
    }
    add_station(adj_list, station2);
}

Subway *create_subway(int num_lines, char **lines) {
    Subway *subway = (Subway*) malloc(sizeof(Subway));
    subway->num_stations = 0;
    subway->adj_lists = (AdjList*) malloc(num_lines * sizeof(AdjList));
    for (int i = 0; i < num_lines; i++) {
        subway->adj_lists[i].head = NULL;
        char *line = lines[i];
        char *station1 = strtok(line, ",");
        char *station2 = strtok(NULL, ",");
        while (station2 != NULL) {
            add_connection(&subway->adj_lists[i], station1, station2);
            add_connection(&subway->adj_lists[i], station2, station1);
            subway->num_stations += 2;
            station1 = station2;
            station2 = strtok(NULL, ",");
        }
    }
    return subway;
}

void print_subway(Subway *subway) {
    printf("Subway:\n");
    for (int i = 0; i < subway->num_stations; i++) {
        printf("%d: ", i);
        Station *station = subway->adj_lists[i / 2].head;
        while (station != NULL && strcmp(station->name, subway->adj_lists[i / 2].head->name) != 0) {
            station = station->next;
        }
        printf("%s\n", station->name);
    }
}

void free_subway(Subway *subway) {
    for (int i = 0; i < subway->num_stations; i++) {
        Station *station = subway->adj_lists[i / 2].head;
        while (station != NULL) {
            Station *next_station = station->next;
            free(station);
            station = next_station;
        }
    }
    free(subway->adj_lists);
    free(subway);
}

int main() {
    char *lines[] = {
        "A1,A2,A3,A4,A5",
        "B1,B2,B3,B4,B5",
        "C1,C2,C3,C4,C5"
    };
    int num_lines = sizeof(lines) / sizeof(char*);
    Subway *subway = create_subway(num_lines, lines);
    print_subway(subway);
    free_subway(subway);
    return 0;
}

这个程序创建了一个简单的地铁系统，包含了三条线路 A、B 和 C，每条线路有 5 个站点。输入的文本格式如下：

A1,A2,A3,A4,A5
B1,B2,B3,B4,B5
C1,C2,C3,C4,C5
END!

程序将文本按逗号分隔，将每个站点添加到相应的邻接表中，然后将每对相邻站点之间的连接添加到邻接表中。最后，程序打印出整个地铁系统的邻接表。