xueji/8.c

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

#define MAX_STUDENT_NUM 100

struct Student {
    char* id;
    char* clas;
    char* name;
    double score1;
    double score2;
    double score3;
    double score;
};

struct Student stu[MAX_STUDENT_NUM];
int stu_num = 0;

void print_menu() {
    printf("1.input\n");
    printf("2.delete\n");
    printf("3.select\n");
    printf("4.order\n");
    printf("5.output\n");
    printf("6.quit\n");
    printf("please input your option\n");
}

void add_student() {
    while (1) {
        printf("Id ");
        stu[stu_num].id = (char*)malloc(sizeof(char) * 20);
        scanf("%s", stu[stu_num].id);
        printf("class ");
        stu[stu_num].clas = (char*)malloc(sizeof(char) * 20);
        scanf("%s", stu[stu_num].clas);
        printf("name ");
        stu[stu_num].name = (char*)malloc(sizeof(char) * 20);
        scanf("%s", stu[stu_num].name);
        printf("score1 ");
        scanf("%lf", &stu[stu_num].score1);
        printf("score2 ");
        scanf("%lf", &stu[stu_num].score2);
        printf("score3 ");
        scanf("%lf", &stu[stu_num].score3);
        stu[stu_num].score = stu[stu_num].score1 + stu[stu_num].score2 + stu[stu_num].score3;
        stu_num++;
        printf("continue? ");
        char answer[10];
        scanf("%s", answer);
        if (strcmp(answer, "no") == 0) {
            break;
        }
    }
}

void delete_student() {
    int i, j;
    while (1) {
        printf("input student id or name to delete\n");
        char query[20];
        scanf("%s", query);
        int deleted = 0;
        for (i = 0; i < stu_num; i++) {
            if (strcmp(query, stu[i].id) == 0 || strcmp(query, stu[i].name) == 0) {
                free(stu[i].id);
                free(stu[i].clas);
                free(stu[i].name);
                for (j = i; j < stu_num - 1; j++) {
                    stu[j] = stu[j + 1];
                }
                stu_num--;
                deleted = 1;
                i--;
            }
        }
        if (!deleted) {
            printf("no such student\n");
        }
        else {
            for (i = 0; i < stu_num; i++) {
                printf("%s,%s,%s,%.1lf,%.1lf,%.1lf,%.1lf\n", stu[i].id, stu[i].clas, stu[i].name, stu[i].score1, stu[i].score2, stu[i].score3, stu[i].score);
            }
        }
        printf("continue? ");
        char answer[10];
        scanf("%s", answer);
        if (strcmp(answer, "no") == 0) {
            break;
        }
    }
}

void select_student() {
    int i;
    while (1) {
        printf("input student id or class to select\n");
        char query[20];
        scanf("%s", query);
        double sum_score1 = 0.0, sum_score2 = 0.0, sum_score3 = 0.0, sum_score = 0.0;
        int count = 0;
        for (i = 0; i < stu_num; i++) {
            if (strcmp(query, stu[i].id) == 0 || strcmp(query, stu[i].clas) == 0) {
                sum_score1 += stu[i].score1;
                sum_score2 += stu[i].score2;
                sum_score3 += stu[i].score3;
                sum_score += stu[i].score;
                count++;
            }
        }
        if (count == 0) {
            printf("no such student\n");
        }
        else {
            printf("average score1: %.1lf\n", sum_score1 / count);
            printf("average score2: %.1lf\n", sum_score2 / count);
            printf("average score3: %.1lf\n", sum_score3 / count);
            printf("average score: %.1lf\n", sum_score / count);
        }
        printf("continue? ");
        char answer[10];
        scanf("%s", answer);
        if (strcmp(answer, "no") == 0) {
            break;
        }
    }
}
void order_student() {
    int i, j;
    while (1) {
        printf("input 1 to order by id or 2 to order by score\n");
        int order_type;
        scanf("%d", &order_type);
        if (order_type != 1 && order_type != 2) {
            printf("invalid order type\n");
            continue;
        }
        for (i = 0; i < stu_num; i++) {
            for (j = i + 1; j < stu_num; j++) {
                if ((order_type == 1 && strcmp(stu[i].id, stu[j].id) > 0) ||
                    (order_type == 2 && stu[i].score < stu[j].score)) {
                    struct Student temp = stu[i];
                    stu[i] = stu[j];
                    stu[j] = temp;
                }
            }
        }
        for (i = 0; i < stu_num; i++) {
            printf("%s,%s,%s,%.1lf,%.1lf,%.1lf,%.1lf\n", stu[i].id, stu[i].clas, stu[i].name, stu[i].score1, stu[i].score2, stu[i].score3, stu[i].score);
        }
        printf("continue? ");
        char answer[10];
        scanf("%s", answer);
        if (strcmp(answer, "no") == 0) {
            break;
        }
    }
}

void output_student() {
    int i;


    for (i = 0; i < stu_num; i++) {
        printf("%s,%s,%s,%.1lf,%.1lf,%.1lf,%.1lf\n", stu[i].id, stu[i].clas, stu[i].name, stu[i].score1, stu[i].score2, stu[i].score3, stu[i].score);
    }

}

int main() {
    while (1) {
        print_menu();
        int option;
        scanf("%d", &option);
        switch (option) {
        case 1:
            add_student();
            break;
        case 2:
            delete_student();
            break;
        case 3:
            select_student();
            break;
        case 4:
            order_student();
            break;
        case 5:
            output_student();
            break;
        case 6:
            printf("goodbye!\n");
            exit(0);
        default:
            printf("invalid option\n");
            break;
        }
    }
    return 0;
}