task2

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

#define N 5 
#define R1 586 
#define R2 701 

int main() 
{ 
	int number; 
	int i; 
	srand( time(0) ); 
	for(i = 0; i < N; ++i)
	{
		number = rand() % (R2 - R1 + 1) + R1;
		printf("20228330%04d\n", number);
	}return 0;
}

　　

取一个R1,R2之间的随机数

生成随机学号

#include<stdio.h>
int main() 
{ 
	double x, y; 
	char c1, c2, c3;
	int a1, a2, a3;
	scanf("%d%d%d", &a1, &a2, &a3);
	printf("a1 = %d, a2 = %d, a3 = %d\n", a1, a2, a3);
	getchar();
	scanf("%c%c%c", &c1, &c2, &c3);
	printf("c1 = %c, c2 = %c, c3 = %c\n", c1, c2, c3); 
	
	scanf("%lf,%lf", &x, &y);
	printf("x = %lf, y = %lf\n", x, y);
	
	return 0;
}

　　

#include <stdio.h>
#include <math.h> 
int main()
{
	double C,F;
	while(scanf("%lf", &C) != EOF)
	{
		F = 9 * C / 5 + 32;
		printf("摄氏度C=%.2lf时,华氏度F=%.2lf\n", C,F);
		printf("\n");
	}
	return 0;
}

#include <stdio.h>
#include <math.h> 
int main()
{
	char a;
	while(scanf("%c", &a) != EOF)
	{
		getchar();
		switch (a)
		{
		case 'r':
			printf("stop!\n"); break;
		case 'g':
			printf("go go go\n"); break;
		case 'y':
			printf("wait a minute\n"); break;
		default:
			printf("some thing must be wrong...\n"); break;
		}
	}
	return 0;
}

　　

#include <stdio.h>
#include <math.h>
#include<stdlib.h>
#include<time.h>
int main()
{
	int a, d,t;
	t = 0;
	srand(time(0));
	a = rand() % 30 + 1;
	printf("猜猜2023年4月那一天会是你的lucky day\n");
	printf("开始了,你有三次机会,猜吧(1-30):");
	scanf("%d", &d);
	for(;a!=d&&t<3;) {
		if (a > d)
			printf("猜早了\n");
		else
			printf("猜晚了\n");
		t = t + 1;
		if (t < 3)
			scanf("%d", &d);
	}
	if (t == 3)
		printf("次数用完了,你的lucky day是%d号", a);
	else
		printf("哇,猜中了");
	return 0;
}

　　

#include <stdio.h>
#include <math.h>
#include<stdlib.h>
#include<time.h>
int main()
{
	int a, b, c;
	a = 1;
	b = 1;
	for (; a<=9;b=1) 
	{
		for (; b <= a;) 
		{
			c = a * b;
			printf("%dx%d=%d ", b, a, c);
			b = b + 1;
         }
		printf("\n");
		a = a + 1;
	}
	return 0;
}

　　

#include <stdio.h>
#include <math.h>
#include<stdlib.h>
#include<time.h>
int main()
{
	int t, a,i;
	for (a = 6; a >= 1;)
	{
		for (i = 1; i <= 6 - a;)
		{
			printf("\t");
			i = i + 1;
		}
		for (t = 1; t <= 2 * a - 1;)
		{
			printf(" o \t");
			t = t + 1;
		}
		printf("\n");
		for (i = 1; i <= 6 - a;)
		{
			printf("\t");
			i = i + 1;
		}
		for (t = 1; t <= 2 * a - 1;)
		{
			printf("<H>\t");
			t = t + 1;
		}
		printf("\n");
		for (i = 1; i <= 6 - a;)
		{
			printf("\t");
			i = i + 1;
		}
		for (t = 1; t <= 2 * a - 1;)
		{
			printf("I I\t");
			t = t + 1;
		}
		printf("\n");
		a = a - 1;
	}
	return 0;
}