实验二

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define N 5
int main()
    {
    int grade,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)
        {
         grade = rand() % 4 + 2018;number = rand() % 999 + 1;
        printf("%d8330%04d\n", grade,number);
        }
    return 0;
    }
                        

1.第16行用于生成2018到2021之间的随机数

2.line17生成001到999之间的随机数

3.随机选人

实验任务二

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#define N 5
int main()
{
    int lucky,day;
    int i;
    lucky = rand() % 30 + 1;
    printf("猜猜2022年4月哪天才是你的lucky day呢\n");
    for (i = 1,day=1;i <= 3;i++)
    {
        if (i == 1)printf("开始咯，你有三次机会，猜吧(1~30):");
        if (i > 1)printf("再猜(1~30):");
        scanf_s("%d",&day);
        if (day == lucky)
        {
            printf("哇，猜对了。");
            break;
        }
        else if (day < lucky)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已经过啦。\n");
    }
    if (i == 4)printf("你的次数用完啦，偷偷告诉你，4月，你的lucky day是%d", lucky);
    
    return 0;
}

实验任务三

#include<stdio.h>
int main()
{
    char light;
    for (;;)
    {
        light = getchar();
        getchar();
        if (light == 'y')printf("wait a minute.\n");
        else if (light == 'r')printf("stop!\n");
        else if (light == 'g')printf("go go go!\n");
        else printf("something must be wrong.\n");
    }
    return 0;
}

 

实验任务四

#include<stdio.h>
int main()
{
    int i, j;
    
    for (;;)
    {        

        double n, a, num, s = 0;

        scanf("%lf %lf", &n, &a);
        printf("n=%lf    a=%lf    ", n, a);
        for (i = 1;i <= n;i++)
        {
            double fenzi = 0, fenmu = 0;
            for (j = 1;j <= i;j++)
            {

                fenzi = fenzi++;
                fenmu = fenmu * 10 + a;
                num = fenzi / fenmu;

            }
            s = s + num;
        }
        printf("s=%lf\n", s);
    }
    return 0;
}

实验任务五

#include<stdio.h>
int main()
{
    int i, j, s;

    for (i = 1;i <= 9;i++)
    {
        for (j = 1;j <= i;j++)
        {
            s = j * i;
            printf("%d*%d=%d    ", i, j, s);
        }
        printf("\n");
    }
    return 0;
}

实验任务六

task6_1

#include<stdio.h>
int main()
{
    int i, n;
    scanf("%d", &n);
    for (i = 1;i <= n;i++)
    {
        printf(" 0 \n<H>\nI I\n\n");
    }
    return 0;
}

 

task6_2

#include<stdio.h>
int main()
{
    int i, n;
    scanf("%d", &n);
    for (i = 1;i <= n;i++)
    {
        printf(" 0        ");
    }
    printf("\n");
    for (i = 1;i <= n;i++)
    {
        printf("<H>        ");
    }
    printf("\n");
    for (i = 1;i <= n;i++)
    {
        printf("I I        ");
    }
    printf("\n");
    return 0;
}

task6_3

#include<stdio.h>
int main()
{
    int i, j, n;
    scanf("%d", &n);
    for (i = 1;i <=n;i++)
    {
        for (j = 1;j < 2 * n;j++)
        {
            if ((j < i) || (j > 2*n-i))printf("   ");
            else printf(" 0 ");
            printf("    ");
        }
        printf("\n");
        for (j = 1;j < 2 * n;j++)
        {
            if ((j < i) || (j > 2 * n - i))printf("   ");
            else printf("<H>");
            printf("    ");
        }
        printf("\n");
        for (j = 1;j < 2 * n;j++)
        {
            if ((j < i) || (j > 2 * n - i))printf("   ");
            else printf("I I");
            printf("    ");
        }
        printf("\n\n");
    }
    return 0;
}