实验2_C语言分枝与循环基础应用编程

试验任务1

task 1.c

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

#define N 5
#define N1 374
#define N2 465

int main()
{
    int number;
    int i;
    
    srand( time(0));
    
    for(i = 0; i < N; ++i){
        number = rand()%(N2 - N1 + 1) + N1;
        printf("202383290376%04d\n", number);        
    }
    
    return 0;
}

//第十七行的作用:生成一个在374到465范围内的随机数
//程序作用：在学号后面随机生成一个四位数，范围在374到465 

试验任务2.c

#include <stdio.h>
int main()
{
    char c;
    
    while(c != EOF)
    {
        printf("请输入信号灯的颜色：（r,g,y 红，绿，黄）");
        scanf("%c", &c);
        getchar();
        switch (c) {
            case 'r':
                printf("stop!\n");
                break;
            case 'g':
                printf("go go go\n");
                break;
            case 'y':
                printf ("wate a minute\n");
                break;        
        }
    }
    return 0; 
}

试验任务3

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

int main(){
    int luckyday = 0;
    int guess;
    int chances = 3;
    
    srand(time(0));
    luckyday = rand() % 30 + 1;
     
    printf("猜猜2023年11月哪一天是你的lucky day\n");
    printf("开始喽，你有三次机会，猜吧(1~30):");
     
    while(chances > 0){
        scanf("%d",&guess);
        
        if (guess == luckyday){
            printf("哇，猜中了:-)\n");
            break;
        }
        else if (guess < luckyday){
            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");    
        }
        
        chances--;    
        
        if(chances > 0){
            printf("再猜(1~30):");
        }
        else{
            printf("次数用完啦。偷偷告诉你：11月，你的lucky day是%d号\n",luckyday);
        }
    }
        return 0;
    }

 试验任务4

#include <stdio.h>

int main(void)
{
    int n, a, b, c;
    double x, s;
    
    while(1 != EOF){
    printf("\n请输入正整数n, a\n");
    scanf("%d",&n);
    scanf("%d",&a);
    
    for(b=1,c=0; b <= n;b++){
        c = c*10 + a;    
        x = 1.0 *b/c;
        s += 1.0 *x; 
       }
    printf("n = %d, a = %d,s = %f",n,a,s);    
    }
    return 0;    
}

 试验任务5

#include <stdio.h>
int main(void)
{
    int a, b, c, n = 9;
    for(a = 1;a < n+1;a++){
        for(b = 1;b < a+1;b++){
            c = b*a;
            printf("%d*%d = %2d  ",b,a,c);
        } 
        printf("\n");       
    }    
 } 

 试验任务6

#include <stdio.h>
int main(void)
{
    int n, a, b, c, d, e, x,t;
    printf("input e:");
    scanf("%d",&e);
    n=(e-1)*2+1;
    x = n;
    
    for(b=1,c=0,t=0;b<=x;b++,c +=2,t+=4){
        for(int j = 1;j <= b-1+t;j++)
            printf(" ");
        for(a=1;a<=n-c;a++){
            printf(" o   ");
        } 
        printf("\n");
        for(int j = 1;j <= b-1+t;j++)
            printf(" ");
        for(a=1;a<=n-c;a++){
            printf("<H>  ");
        }
        printf("\n");
       for(int j = 1;j <= b-1+t;j++)
            printf(" ");
        for(a=1;a<=n-c;a++){
            printf("I I  ");
        }
        printf("\n");
        
        
    }
    
    return 0;    
 }