//乘客节点 typedef struct CustomerNode { char name[10];//客户姓名 int clientTickets;//客户订票量 char identification[20];//客户身份证号码 int rank;//座位等级 CustomerNode *next; } CustomerNode, *CusLinkList; //候补队列中的节点 typedef struct WaitPassenger { char name[10];//姓名 char identification[20]; //身份证 int preTickets;//预定的票量 struct WaitPassenger *next; } WaitQNode, *PWait; typedef struct CusLinkList2{ CusLinkList head;//头指针 int count;//链表长度 } CusLinkList2; //候补队列 typedef struct Queue { PWait front;//等候替补客户名单域的头指针 PWait rear;//等候替补客户名单域的尾指针 } LinkQueue; //封装乘客的姓名和订票量和身份证 //用于候补客户出队时把关键字返回 typedef struct NameAndNumAndID { char name[10];//姓名 char identification[20]; //身份证号码 int num;//订票量 } NameAndNumAndID; //车次节点 typedef struct Flight { char startPoint[20];//起点站名 char destination[20];//终点站名 char flightCodeID[20];//车次ID（相当于主键） char planeNum[20];//列车号 char day[20];//出发日期（星期几） int totalTickets;//乘员定额(总票数) int left;//总余票量 int leftEconomicTicket; //二等座剩余量 int leftBusinessTicket; //一等座剩余量 Flight *next; CusLinkList cusLinkList;//乘员名单域，指向乘员名单链表的头指针 LinkQueue waitQueue1;//二等座候补，等候替补的客户名单域，指向一个队列 LinkQueue waitQueue2;//一等座候补，等候替补的客户名单域，指向一个队列 } Flight, FlightNode, *PFlight;用c语言实现该结构体的文件读取操作，并写出具体代码

假设我们需要从一个名为"flight.txt"的文件中读取Flight结构体的信息，以下是具体的代码实现：

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

#define MAX_LEN 100 //最大行长

//乘客节点
typedef struct CustomerNode {
    char name[10];//客户姓名
    int clientTickets;//客户订票量
    char identification[20];//客户身份证号码
    int rank;//座位等级
    CustomerNode *next;
} CustomerNode, *CusLinkList;

//候补队列中的节点
typedef struct WaitPassenger {
    char name[10];//姓名
    char identification[20]; //身份证
    int preTickets;//预定的票量
    struct WaitPassenger *next;
} WaitQNode, *PWait;

typedef struct CusLinkList2{
    CusLinkList head;//头指针
    int count;//链表长度
} CusLinkList2;

//候补队列
typedef struct Queue {
    PWait front;//等候替补客户名单域的头指针
    PWait rear;//等候替补客户名单域的尾指针
} LinkQueue;

//封装乘客的姓名和订票量和身份证
//用于候补客户出队时把关键字返回
typedef struct NameAndNumAndID {
    char name[10];//姓名
    char identification[20]; //身份证号码
    int num;//订票量
} NameAndNumAndID;

//车次节点
typedef struct Flight {
    char startPoint[20];//起点站名
    char destination[20];//终点站名
    char flightCodeID[20];//车次ID（相当于主键）
    char planeNum[20];//列车号
    char day[20];//出发日期（星期几）
    int totalTickets;//乘员定额(总票数)
    int left;//总余票量
    int leftEconomicTicket; //二等座剩余量
    int leftBusinessTicket; //一等座剩余量
    Flight *next;
    CusLinkList cusLinkList;//乘员名单域，指向乘员名单链表的头指针
    LinkQueue waitQueue1;//二等座候补，等候替补的客户名单域，指向一个队列
    LinkQueue waitQueue2;//一等座候补，等候替补的客户名单域，指向一个队列
} Flight, FlightNode, *PFlight;

//从文件中读取一行数据
char* readLine(FILE* fp) {
    char* line = (char*)malloc(MAX_LEN * sizeof(char));
    if (!line) {
        perror("Memory allocation failed!");
        exit(1);
    }
    if (fgets(line, MAX_LEN, fp) == NULL) {
        free(line);
        return NULL;
    }
    int len = strlen(line);
    if (len > 0 && line[len - 1] == '\n') {
        line[len - 1] = '\0';
    }
    return line;
}

//从文件中读取一个Flight结构体的信息
PFlight readFlightFromFile(FILE* fp) {
    char* line;
    PFlight flight = (PFlight)malloc(sizeof(FlightNode));
    if (!flight) {
        perror("Memory allocation for flight failed!");
        exit(1);
    }
    flight->cusLinkList.head = NULL;
    flight->waitQueue1.front = flight->waitQueue2.front = NULL;
    flight->waitQueue1.rear = flight->waitQueue2.rear = NULL;
    flight->next = NULL;
    while ((line = readLine(fp)) != NULL) {
        if (strncmp(line, "startPoint:", 11) == 0) {
            strcpy(flight->startPoint, line + 11);
        }
        else if (strncmp(line, "destination:", 12) == 0) {
            strcpy(flight->destination, line + 12);
        }
        else if (strncmp(line, "flightCodeID:", 13) == 0) {
            strcpy(flight->flightCodeID, line + 13);
        }
        else if (strncmp(line, "planeNum:", 9) == 0) {
            strcpy(flight->planeNum, line + 9);
        }
        else if (strncmp(line, "day:", 4) == 0) {
            strcpy(flight->day, line + 4);
        }
        else if (strncmp(line, "totalTickets:", 13) == 0) {
            flight->totalTickets = atoi(line + 13);
            flight->left = flight->totalTickets;
        }
        else if (strncmp(line, "left:", 5) == 0) {
            flight->left = atoi(line + 5);
        }
        else if (strncmp(line, "leftEconomicTicket:", 19) == 0) {
            flight->leftEconomicTicket = atoi(line + 19);
        }
        else if (strncmp(line, "leftBusinessTicket:", 19) == 0) {
            flight->leftBusinessTicket = atoi(line + 19);
        }
        else if (strncmp(line, "cusLinkList:", 12) == 0) {
            //读取乘员名单域
            CusLinkList cusList = &flight->cusLinkList;
            cusList->count = 0;
            while ((line = readLine(fp)) != NULL && strncmp(line, "waitQueue1:", 11) != 0 && strncmp(line, "waitQueue2:", 11) != 0) {
                CustomerNode* cus = (CustomerNode*)malloc(sizeof(CustomerNode));
                if (!cus) {
                    perror("Memory allocation for customer failed!");
                    exit(1);
                }
                sscanf(line, "%s %d %s %d", cus->name, &cus->clientTickets, cus->identification, &cus->rank);
                cus->next = cusList->head;
                cusList->head = cus;
                cusList->count++;
            }
            if (line != NULL && strncmp(line, "waitQueue1:", 11) == 0) {
                //读取二等座候补队列
                LinkQueue* queue = &flight->waitQueue1;
                while ((line = readLine(fp)) != NULL && strncmp(line, "waitQueue2:", 11) != 0) {
                    PWait waitNode = (PWait)malloc(sizeof(WaitQNode));
                    if (!waitNode) {
                        perror("Memory allocation for wait passenger failed!");
                        exit(1);
                    }
                    sscanf(line, "%s %s %d", waitNode->name, waitNode->identification, &waitNode->preTickets);
                    waitNode->next = NULL;
                    if (queue->front == NULL) {
                        queue->front = waitNode;
                    }
                    else {
                        queue->rear->next = waitNode;
                    }
                    queue->rear = waitNode;
                }
            }
            if (line != NULL && strncmp(line, "waitQueue2:", 11) == 0) {
                //读取一等座候补队列
                LinkQueue* queue = &flight->waitQueue2;
                while ((line = readLine(fp)) != NULL) {
                    PWait waitNode = (PWait)malloc(sizeof(WaitQNode));
                    if (!waitNode) {
                        perror("Memory allocation for wait passenger failed!");
                        exit(1);
                    }
                    sscanf(line, "%s %s %d", waitNode->name, waitNode->identification, &waitNode->preTickets);
                    waitNode->next = NULL;
                    if (queue->front == NULL) {
                        queue->front = waitNode;
                    }
                    else {
                        queue->rear->next = waitNode;
                    }
                    queue->rear = waitNode;
                }
            }
        }
    }
    return flight;
}

//从文件中读取多个Flight结构体的信息
PFlight readFlightsFromFile(char* fileName) {
    FILE* fp = fopen(fileName, "r");
    if (!fp) {
        perror("Failed to open file!");
        exit(1);
    }
    PFlight head = NULL;
    PFlight tail = NULL;
    while (!feof(fp)) {
        PFlight flight = readFlightFromFile(fp);
        if (flight != NULL) {
            if (head == NULL) {
                head = flight;
            }
            else {
                tail->next = flight;
            }
            tail = flight;
        }
    }
    fclose(fp);
    return head;
}

int main() {
    PFlight flights = readFlightsFromFile("flight.txt");
    //对读取到的Flight结构体进行操作
    //...
    return 0;
}