作业二

#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;
}

#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int main()
{
    int i, number,n;
    srand(time(0));
    number = rand() % 30 + 1;
    printf("猜猜2022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):"); 
    scanf_s("%d", &i);
    for (n = 1; n <= 2; n++)
    {
        if (i == number)
        {
            printf("哇，猜中了");
            break;
        }
        else if (i > number) {
            printf("你猜的日期晚了，你的lucky day已经过啦\n");
            scanf_s("%d", &i);
            printf("再猜(1~30):%d", i);
        }
        else if (i < number) {
            printf("你猜的日期早了，你的lucky day还没到呢\n");
            scanf_s("%d", &i);
            printf("再猜（1~30）：%d", i);
        }
    } 
    if (n >= 2) {
        printf("次数用完了，偷偷告诉你：11月，你的lucky day是：%d", number);
    }
    return 0;


}

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



}

#include<stdio.h>
#include<math.h>
#include<stdlib.h>
int main()
{
        int a, n;
        double  m, z, s, i;
        m = 0;
        while (scanf_s("%d%d", &n, &a) != EOF)
        {
            s = 0;
            m = 0;
            for (z = 1; z <= n; z++)
            {
                m = a * pow(10,z-1) + m;
                i = z * 1.0 / m;
                s = s + i;
            }
            printf("n=%d,a=%d,s=%lf", n, a, s);
        }
    return 0;
}

#include<stdio.h>
int main()
{
    int i = 0;
    int j = 0;
    for (j = 1; j <= 9; j++) {
        for (i = 1; i <= j; i++) {
            printf("%d*%d=%-4d", j, i, i * j);
        }
        printf("\n");
    }
    return 0;

#include<stdio.h>
int main()
{
    int m, n, i;
    scanf_s("%d", &n);
    printf("input:%d\n", n);
    for (i = 1; i <= n; i++) {
        for (m = 1; m <= i - 1; m++) {
            printf("\t");
        }
        for (m = 1; m <= (2 * n - 2 * i + 1); m++)
        {
            printf(" o \t");

        }
        printf("\n");
        for (m = 1; m <= i - 1; m++) {
            printf("\t");
        }
        for (m = 1; m <= (2 * n - 2 * i + 1); m++) {
            printf("<H>\t");
        }
        printf("\n");
        for (m = 1; m <= i - 1; m++) {
            printf("\t");
        }
        for (m = 1; m <= (2 * n - 2 * i + 1); m++)
        {
            printf("I I\t");
        }
        printf("\n");
    }
    return 0;
}