实验2

实验任务1

include <stdio.h>

include <stdlib.h>

include <time.h>

define N 5

define N1 397

define N2 476

define N3 21

int main() {
int cnt;
int random_major, random_no;

srand(time(NULL));

cnt = 0;
while(cnt < N) {
    random_major = rand() % 2;
    
    if(random_major){
	    random_no = rand() % (N2-N1+1) + N1;
	    printf("20248329%04d\n", random_no);

}
else{
random_no = rand() % N3 + 1;
printf("20248329%04d\n", random_no);

	}
	
	
	cnt++;

}

  return 0;

}
line21功能：生成N1-N2的整数
line25功能：生成N2-N3的整数
程序功能：随机生成学号

实验任务2

include <stdio.h>

include <math.h>

int main (){
double a,b,c;
double delta,p1,p2;

while(scanf("%lf%lf%lf", &a, &b, &c) != EOF) {
	if(a == 0){
		printf("a = 0, invalid input\n");		
		continue;
		
		}
		delta =b*b -4*a*c;
		p1 = -b/2/a;
		p2 = sqrt(fabs(delta))/2/a;
		
		if(delta == 0)
		    printf("x1 = %.2g,x2 = %.2g\n",p1+p2,p1-p2);
		else if(delta > 0)
		    printf("x1 = %.2g, x2 = %.2g\n",p1+p2,p1-p2);
		else{
			printf("x1 = %.2g + %.2gi,",p1,p2);
			printf("x2 = %.2g - %.2gi,",p1,p2);
		}
}
return 0;

}
实验任务3

include<stdio.h>

int main()
{
char color;
while((color = getchar()) !=EOF){
if (color == 'r'){
printf("stop!\n");}
else if (color == 'y'){
printf("wait a minute\n");}
else if(color == 'g'){
printf("go go go\n");}
else{
printf("something must be wrong...\n");}
getchar();
}

return 0;

}
实验任务4

include<stdio.h>

int main()
{
printf("输入今日开销，直到输入-1时终止:\n");
double cost, maxcost = 0,mincost = 20000, totalcost = 0;
while(scanf("%lf",&cost) != EOF){
if(cost == -1){
break;}
if(cost > maxcost){
maxcost = cost;
}
if(cost < mincost && cost > 0){
mincost = cost;
}
totalcost += cost;
}
printf("最高一笔开销:%.1lf\n",maxcost);
printf("最低一笔开销:%.1lf\n",mincost);
printf("累计消费总额:%.1lf\n",totalcost);

	return 0;
}

实验任务5

include<stdio.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){
printf("可以构成普通三角形\n");}
else{
printf("不能构成三角形\n");
return 0;}
if(a * a + b * b == c * c || a * a + c * c == b * b || b * b + c * c == a * a){
printf("可以构成直角三角形\n");}
else
if(a == b || a == c || b == c){
printf("可以构成等腰三角形\n");}
else
if(a == b == c){
printf("可以构成等边三角形\n");
}
}
return 0;

}
实验任务6

include<stdio.h>

include<stdlib.h>

include<time.h>

int main()
{
int day,luckyday,i = 3;
printf("猜猜2024年11月哪一天会是你的lucky day\n");
printf("开始喽，你有三次机会，猜吧:(1-30)");
srand(time(NULL));
luckyday = rand() % 30 + 1;
while (i > 0);{
scanf("%d",&day);
if(day == luckyday) {
printf("哇，猜中了");
return 0;
}
else if(day < luckyday){
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在前面呢\n");
printf("再猜：（1-30）");
}

   i--;}
   printf("次数用光啦，悄悄告诉你，你的lucky day是%d\n", luckyday);
   return 0;

}