实验2

include <stdio.h>

include <stdlib.h>

include <time.h>

define N 100

define CNT 5

int main() {
  int number;
  int i;
  srand(time(0));   // 以当前系统时间作为随机种子
  for(i = 0; i < N; ++i) {
    number = rand() % 100 + 1;
    printf("20490042%04d\n", number);
 }
  return 0;
}

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;
}

include <stdio.h>

int main() {
char c;
for (int i = 0; i < 4; i++) {
scanf_s("%c", &c);
getchar();

switch (c) {
case 'r':
printf("stop!\n");
break;
case 'g':
printf("go go go\n");
break;
case 'y':
printf("wait a minute\n");
break;
default:
printf("something must be wrong...\n");
break;
}
}
return 0;
}

include <stdio.h>

int main() {
float cost;
float sum = 0.0;
float max_cost = 0.0;
float min_cost = 20000.0;

printf("输入今日开销，直到输入-1终止：\n");

while (1) {
scanf_s("%f", &cost);
if (cost == -1) {
break;
}
sum += cost;
if (cost > max_cost) {
max_cost = cost;
}
if (cost < min_cost) {
min_cost = cost;
}
}
printf("今日累计消费总额：%.1f\n", sum);
printf("今日最高一笔开销：%.1f\n", max_cost);
printf("今日最低一笔开销：%.1f\n", min_cost);

return 0;
}

include <stdio.h>

int main() {
int a, b, c;
for(int i = 0; i < 5; i++) {
scanf("%d %d %d", &a, &b, &c);
if(a + b <= c || a + c <= b || b + c <= a) {
printf("不能构成三角形\n");
continue; }
if(a == b && b == c) {
printf("等边三角形\n");
}
else if(a == b || b == c || a == c) {
printf("等腰三角形\n");
}
else if(aa + bb == cc || aa + cc == bb || bb + cc == a*a) {
printf("直角三角形\n");
}
else {
printf("普通三角形\n");
}
}

return 0;
}

include <stdio.h>

include <stdlib.h>

include <time.h>

int main() {
// 初始化随机数种子，保证每次运行生成的随机数不一样
srand((unsigned int)time(NULL));
// 生成1-30之间的随机整数作为lucky day
int lucky_day = rand() % 30 + 1;
int guess;

printf("猜猜2026年11月哪一天是你的lucky day\n");

// 循环3次，对应3次猜的机会
for(int i = 0; i < 3; i++) {
if(i == 0) {
printf("开始喽，你有3次机会，猜吧(1~30): ");
} else {
printf("再猜(1~30): ");
}
scanf("%d", &guess);

if(guess == lucky_day) {
printf("哇，猜中了:)\n");
return 0; // 猜中直接结束程序
} else if(guess < lucky_day) {
printf("你猜的日期早了，你的lucky day还没到呢\n");
} else {
printf("你猜的日期晚了，你的lucky day在前面哦\n");
}
}

// 3次都没猜中，输出正确答案
printf("次数用光啦。11月你的lucky day是%d号\n", lucky_day);

return 0;
}