实验二

 问题一：确保不同时间所生成的数据不同，不会出现重复

问题二：依据时间随机生成不同的学号

 

实验任务二

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
int main() {
    int choice, quantity;
    float total_price = 0, amount_paid, change;
    while (1) {
        printf("\n自动饮料售卖机菜单:\n");
        printf("1. 可乐 - 3 元/瓶\n");
        printf("2. 雪碧 - 3 元/瓶\n");
        printf("3. 橙汁 - 5 元/瓶\n");
        printf("4. 矿泉水 - 2 元/瓶\n");
        printf("0. 退出购买流程\n");
        printf("请输入饮料编号: ");
        scanf("%d", &choice);
        if (choice == 0)
            break;
        if (choice < 1 || choice > 4) {
            printf("无效的饮料编号，请重新输入。\n");
            continue;
        }
        printf("请输入购买的数量: ");
        scanf("%d", &quantity);
        if (quantity < 0) {
            printf("购买数量不能为负数，请重新输入。\n");
            continue;
        }
        if (choice == 1 || choice == 2)
            total_price += 3 * quantity;
        else if (choice == 3)
            total_price += 5 * quantity;
        else
            total_price += 2 * quantity;
        printf("请投入金额: ");
        scanf("%f", &amount_paid);
        change = amount_paid - total_price;
        printf("本次购买总价: %.2f 元\n", total_price);
        printf("找零: %.2f 元\n", change);
        total_price = 0;
    }
    printf("感谢您的购买，欢迎下次光临！\n");

    return 0;
}

问题一：下次循环会使用已被赋值的total_price

问题二：在符合并运行当前分支程序后，仍继续往下运行当前循环

实验任务三

 

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include<stdlib.h>
int main() {
    char ans;
    while (scanf("%c", &ans) != EOF) {
        if (ans == 'r')
            printf("stop\n");
        else if (ans == 'g') {
            printf("go go go\n");
        }
        else if (ans == 'y') {
            printf("wait a minute\n");
        }
        else
            printf("something must be wrong\n");
        ans = getchar();
    }

    return 0;
}

 

实验任务四

 

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include<stdlib.h>
int main() {
    double a;
    double max = 0;
    double min = 20000;
    double total = 0;
    printf("输入今日开销，直至输入-1为止：\n");
    
    while (1) {
        scanf("%lf", &a);
        if (a == -1) {
            break;
        }
        total += a;
        if (a > max) {
            max = a;
        }
        if (a < min) {
            min = a;
        }

    }
    printf("今日累计消费总额：%.1lf\n", total);
    printf("今日最高一笔开销：%.1lf\n", max);
    printf("今日最低一笔开销：%.1lf\n", min);

    return 0;
}

实验任务五

 

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include<stdlib.h>
int main() {
    int a, b, c;
    while (scanf("%d%d%d", &a, &b, &c)!=EOF) {
        if (a + b > c && a + c > b && b + c > a) {
            if (a * a + b * b == c * c || a * a + c * c == b * b || b * b + c * c == a * a)
                printf("直角三角形\n");
            else if (a == b && b == c)
                printf("等边三角形\n");
            else if (a == b || a == c || b == c)
                printf("等腰三角形\n");
            else
                printf("普通三角形\n");
        }
        else
            printf("不能构成三角形\n");
    }

    return 0;
}

 

实验任务六

 

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include<stdlib.h>
int main() {
    int day, n, i;
    i = 0;
    srand(time(NULL));
    day = rand() % 30 + 1;
    printf("猜猜2025年11月哪一天是你的lucky day\n");
    printf("开始喽，你有3次机会,猜吧(1~30）：");
    while (i < 3) {
        scanf("%d", &n);
        if (day == n) {
            printf("哇，猜中了");
            break;
        }
        else if (n < day) {
            printf("你猜的日期早了，你的lucky day还没到呢\n");
            printf("再猜（1~30）：");
        }
        else {
            printf("你猜的日期晚了，你的lucky day在前面哦\n");
            printf("再猜（1~30）：");
        }
        if (i == 2) {
            printf("次数用光啦。偷偷告诉你，11月你的lucky day是 % d", day);
        }
        ++i;
    }

    return 0;
}