用c编写程序开始时，自动从文件读入信息到结构体数组，并提取每个公民的出生年月放入结构体中，同时进行身份证校验位是否正确，判断信息也放入结构体中。补全主函数，#include <stdio.h> #include <string.h> #define N 100 struct birth { int year; int month; int day; }; struct person { char ID[19]; char name[20]; struct birth birthday; int flag;//校验位是否正确, 1代表正确，0代表错误 }; int read(struct person p[]); int checkID(char *ID); struct birth get_birth(char *ID); void get_all_person(struct person p[], int n); void display_person(struct person p[], int n, int flag); int birth_cmp(struct birth birth1, struct birth birth2); void birth_sort(struct person p[], int n); int search(struct person p[], int n, char *name); void save(struct person p[], int n); int prompt(void); int main(void) { struct person p[N]; int cmd, n; while (1) { cmd = prompt(); } return 0; }

补全的代码如下：

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

#define N 100 

struct birth {
    int year;
    int month;
    int day;
};

struct person {
    char ID[19];
    char name[20];
    struct birth birthday;
    int flag; // 校验位是否正确, 1代表正确，0代表错误
};

int read(struct person p[]);
int checkID(char *ID);
struct birth get_birth(char *ID);
void get_all_person(struct person p[], int n);
void display_person(struct person p[], int n, int flag);
int birth_cmp(struct birth birth1, struct birth birth2);
void birth_sort(struct person p[], int n);
int search(struct person p[], int n, char *name);
void save(struct person p[], int n);
int prompt(void); 

int main(void) {
    struct person p[N];
    int cmd, n; 
    
    while (1) {
        cmd = prompt();
        switch (cmd) {
            case 1: 
                n = read(p);
                break;
            case 2:
                get_all_person(p, n);
                break;
            case 3:
                birth_sort(p, n);
                break;
            case 4:
                display_person(p, n, 1);
                break;
            case 5:
                display_person(p, n, 0);
                break;
            case 6: 
                save(p, n);
                break;
            case 7:
                return 0;
            default:
                printf("Invalid command!\n");
                break;
        }
    }
    
    return 0;
}

int read(struct person p[]) {
    FILE *fp;
    char filename[20];
    int i = 0;
    
    printf("Enter the file name: ");
    scanf("%s", filename);
    
    fp = fopen(filename, "r");
    if (!fp) {
        printf("Failed to open file!\n");
        return 0;
    }
    
    while (fscanf(fp, "%s %s", p[i].ID, p[i].name) != EOF) {
        p[i].birthday = get_birth(p[i].ID);
        p[i].flag = checkID(p[i].ID);
        i++;
    }
    
    fclose(fp);
    printf("Read file successfully!\n");
    
    return i;
}

int checkID(char *ID) {
    int i, sum = 0, weight;
    int weight_list[] = {7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2, 1};
    char check_list[] = "10X98765432";
    
    for (i = 0; i < 17; i++) {
        sum += (ID[i] - '0') * weight_list[i];
    }
    
    weight = sum % 11;
    
    if (ID[17] == check_list[weight]) {
        return 1;
    } else {
        return 0;
    }
}

struct birth get_birth(char *ID) {
    struct birth birthday;
    
    birthday.year = (ID[6] - '0') * 1000 + (ID[7] - '0') * 100 + (ID[8] - '0') * 10 + (ID[9] - '0');
    birthday.month = (ID[10] - '0') * 10 + (ID[11] - '0');
    birthday.day = (ID[12] - '0') * 10 + (ID[13] - '0');
    
    return birthday;
}

void get_all_person(struct person p[], int n) {
    int i;
    
    printf("All persons:\n");
    for (i = 0; i < n; i++) {
        printf("%s %s %d-%02d-%02d %s\n", p[i].ID, p[i].name, p[i].birthday.year, p[i].birthday.month, p[i].birthday.day, p[i].flag ? "correct" : "incorrect");
    }
}

void display_person(struct person p[], int n, int flag) {
    int i;
    
    printf("Persons with %s ID:\n", flag ? "correct" : "incorrect");
    for (i = 0; i < n; i++) {
        if (p[i].flag == flag) {
            printf("%s %s %d-%02d-%02d\n", p[i].ID, p[i].name, p[i].birthday.year, p[i].birthday.month, p[i].birthday.day);
        }
    }
}

int birth_cmp(struct birth birth1, struct birth birth2) {
    if (birth1.year != birth2.year) {
        return birth1.year - birth2.year;
    } else if (birth1.month != birth2.month) {
        return birth1.month - birth2.month;
    } else {
        return birth1.day - birth2.day;
    }
}

void birth_sort(struct person p[], int n) {
    int i, j;
    struct person temp;
    
    for (i = 0; i < n; i++) {
        for (j = i + 1; j < n; j++) {
            if (birth_cmp(p[i].birthday, p[j].birthday) > 0) {
                temp = p[i];
                p[i] = p[j];
                p[j] = temp;
            }
        }
    }
    
    printf("Sort by birthday successfully!\n");
}

int search(struct person p[], int n, char *name) {
    int i;
    
    for (i = 0; i < n; i++) {
        if (strcmp(p[i].name, name) == 0) {
            return i;
        }
    }
    
    return -1;
}

void save(struct person p[], int n) {
    FILE *fp;
    char filename[20];
    int i;
    
    printf("Enter the file name: ");
    scanf("%s", filename);
    
    fp = fopen(filename, "w");
    if (!fp) {
        printf("Failed to create file!\n");
        return;
    }
    
    for (i = 0; i < n; i++) {
        fprintf(fp, "%s %s %d-%02d-%02d %s\n", p[i].ID, p[i].name, p[i].birthday.year, p[i].birthday.month, p[i].birthday.day, p[i].flag ? "correct" : "incorrect");
    }
    
    fclose(fp);
    printf("Save file successfully!\n");
}

int prompt(void) {
    int cmd;
    
    printf("\nMenu:\n");
    printf("1. Read from file\n");
    printf("2. Display all persons\n");
    printf("3. Sort by birthday\n");
    printf("4. Display persons with correct ID\n");
    printf("5. Display persons with incorrect ID\n");
    printf("6. Save to file\n");
    printf("7. Quit\n");
    printf("Enter a command: ");
    scanf("%d", &cmd);
    
    return cmd;
}