SY2

TASK1` #include <stdio.h>

include <stdlib.h>

include <time.h>

define N 5

define N1 80

define N2 35

int main() {
int cnt;
int random_major, random_no;
srand(time(NULL)); // 以当前系统时间作为随机种子
cnt = 0;
while(cnt < N) {
random_major = rand() % 2;
if(random_major) {
random_no = rand() % N1 + 1;
printf("20256343%04d\n", random_no);
}
else {
random_no = rand() % N2 + 1;
printf("20256136%04d\n", random_no);
}
cnt++;
}
return 0;
} @answer1(使rand函数的种子随时间变化） @answer2（每次根据第一个随机数生成1-35或1-80的随机数） TASK 2#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;
}
@answer1(使总价初始为0） @answer1（直接进入循环 TASK3 #include<stdio.h>
int main()
{
char c;
while (scanf_s(" %c", &c, 1) != EOF) {
if (c == 'r')
printf("stop\n");
else if (c == 'g')
printf("go go go\n");
else if (c == 'y')
printf("wait a minute");
else(printf("something must be wrong"));
}
}![屏幕截图 2025-10-17 173507](https://img2024.cnblogs.com/blog/3707955/202510/3707955-20251017173545524-1203700205.png) TASK4#include<stdio.h>
int main() {
double a, sum = 0, max = 0, min = 20000, b = 1;
while (1) {
scanf_s("%lf", &a);
if (a == -1)break;
sum += a;
if (b == 1)max = 0, min = 20000, b = 0;
else {
if (a > max) max = a;
else if (a < min)min = a;

	}
}
printf("最高一笔开销:%lf\n", max);
printf("最低一笔开销:%lf\n", min);
printf("一天总开销%lf\n", sum);

}![屏幕截图 2025-10-14 161421](https://img2024.cnblogs.com/blog/3707955/202510/3707955-20251017173757598-1967248671.png) TASK5#include<stdio.h>
int main()
{
int a, b, c, y;
while (scanf_s("%d%d%d",&a,&b,&c) != EOF)
{
if (a < 0 || b < 0 || c < 0)
printf("不能构成三角形\n");
else if ((a + b) <= c || (a + c) < b || (c + b) < a)
printf("不能构成三角形/n");
else if (a == b && a == c && b == c)
printf("等边三角形/n");
else if (a * a == b * b + c * c || b * b == c * c + a * a || c * c == a * a + b * b)
printf("直角三角形/n");
else if (a == b || b == c || a == c)
printf("等腰三角形/n");
else(printf("普通三角形/n"));
}
}![屏幕截图 2025-10-16 195828](https://img2024.cnblogs.com/blog/3707955/202510/3707955-20251017173941037-494534344.png) task6#include<stdio.h>

include<stdlib.h>

include<time.h>

int main()
{
int b, c, d;
srand((unsigned int)time(NULL));
int a = rand() % 30;
printf("有3次猜的机会,选[1, 30]之间一个随机整数作为11月的lucky day: \n");
for (d = 0; d < 3; ++d) {
scanf_s("%d", &c);
if (c == a)
printf("答对\n");
else if (c < a)
printf(("答错，在后面\n"));
else (printf("答错，在前面\n"));
}printf("次数用尽，your lucky day is:%d",a);
}`