Task1

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

#define N 5
int main()
{
    int number;
    int i;

    srand(time(0));

    for (i=0;i<N;++i)
    {
        number = rand() % 500 + 1;
        printf("20228329%04d\n", number);

    }
    return 0;
}

随机生成一个范围在1~500以内的整数

随机生成5个同学的学号

Task2

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

int main()
{
    int i = 1,s =0;
    int number;
    int x;
    number = rand() % 30 + 1;
    printf("猜猜2022年11月哪一天会是你的lucky day\n开始喽,你有三次机会,猜吧(1~30):");
    
    for (; i <= 3; i++) {
        s++;
        scanf_s("%d", &x);
        if (x != number) {
            if (x < number)
                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");
        }
        else
        {
            printf("哇,猜中了\n"); break;
        }
        if (i < 3)
            printf("再猜(1~30):");
        }
    if (s = 3)
    {
        printf("次数用完啦,偷偷告诉你:11月你的lucky day是:%d", number);
    }
    return 0;
    }
    

Task3

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

Task4

#include<stdio.h>
#include<math.h>
int main()
{
    int x ;
    int n, a;
    double s=0,u=0;
    do {
        scanf_s("%d%d", &n, &a);
        for (x=1; x <= n; x++)
        {
            u += a * pow(10, (x - 1));
            s += x / u;

        }
    printf("n=%d,a=%d,s=%lf\n", n, a, s);
    s = 0;
    u = 0;
    } while (getchar() != EOF);

    return 0;
}

 Task5

#include<stdio.h>

int main() {
    int x, y;
    for (x = 1; x <= 9; x++) {
        for (y = 1; y <= x; y++) {
            printf("%d*%d=%-3d", x, y, x * y);
        }
        printf("\n");
    }
    return 0;
}

Task6

#include<stdio.h>

int main()
{
    int n;
    printf("imput:");
    scanf_s("%d", &n);

    int total = 2 * n - 1;
    for (int i = 0; i < n; i++) {

        for (int t = 1; t <= total; t++)
        {
            if (t > i && t < 2 * n - i)
                printf(" o\t");
            else printf("\t");
            if (t == total)
                printf("\n");
        }
        for (int t = 1; t <= total; t++)
        {
            if (t > i && t < 2 * n - i)
                printf("<H>\t");
            else printf("\t");
            if (t == total)
                printf("\n");
        }
        for (int t = 1; t <= total; t++)
        {
            if (t > i && t < 2 * n - i)
                printf("I I\t");
            else printf("\t");
            if (t == total)
                printf("\n");
        }
        printf("\n");
    }
    return 0;
}

当输入为n时:

第i行,需要打印 (2n-2i+1)个小人

第i行,前面需要打印(i-1)个空白