吴云行的实验二

//p1改错
#include <stdio.h>
int main() {
    double x,y;
    char c1,c2,c3;
    int a1,a2,a3;
    
    scanf("%d%d%d",&a1,&a2,&a3);
    printf("%d %d %d\n",a1,a2,a3);
    
    
    scanf("%c%c%c",&c1,&c2,&c3);
    printf("%c%c%c\n",c1,c2,c3);
    
    
    scanf("%lf,%lf",&x,&y);
    printf("%lf,%lf\n",x,y);
    return 0;
} 

//p2验证三角形，没有问题 
 #include <stdio.h>
 int main() {
     double a,b,c;
     scanf("%lf %lf %lf", &a, &b, &c);
     
     if(a<0 || b<0 || c<0)
         printf("不能构成三角形\n");
     else if(a+b>c && a+c>b && b+c>a)
      {
          
        if(a==b || a==c || b==c) 
        { 
           if (a==b && a==c) 
        printf("构成等边三角形\n");
           else
           printf("构成等腰三角形\n"); 
        } 
      else
        printf("构成一般三角形\n");
     }
     else
         printf("不能构成三角形\n");
         
     return 0;
} 

//p2 char变int
#include <stdio.h>
#include <stdlib.h>
int main() {
    int choice;
    
    // 显示菜单 
    printf("输入0~9以内的数字，选择屏幕背景色前景色方案: \n");
    printf("1-\t黑底绿色\n");
    printf("2-\t白底黑色\n");
    printf("3-\t蓝底白色\n");
    printf("其它-\t黑底白色(默认)\n");
    printf("\n请输入, 选择你想使用的屏幕配色方案:    ");
    
    // 要求用户从键盘输入0~9的数字，选择屏幕配色方案 
    scanf("%d",&choice);
    
    // 根据用户输入，设置屏幕配色方案 
    if (choice == 1) {
        system("color 02");
        printf("《黑客帝国》一类的影视剧常见这种屏幕色:)\n"); 
    } 
        
    else if(choice == 2) {
        system("color f0");
        printf("大部分编辑器默认是这种配色:)\n");    
    }
        
    else if(choice == 3) {
        system("color 1f");
        printf("这是机器蓝屏故障时的不讨喜色:)\n");
    }
        
    else {
        system("color 0f");
        printf("控制台程序默认小黑窗:)\n");        
    }
        
        
    printf("programming is fun, just try@_@\n");
    
    
    return 0;

}

//p3练习1
#include<stdio.h>
int main(){
    int a ;
    
    printf("请输入一个三为以内的十进制整数：");
    scanf("%d",&a);
    printf("计算其逆序数...\n");
    
    
    if (a>=0&&a<=9)
    printf("%d正序和逆序相同\n",a);
    
    else if(a>=10&&a<=99){
        if(a/10==a-a/10*10)
        printf("%d正序和逆序相同\n",a);
        else 
        printf("%d正序和逆序不同\n",a);
    }
    else{
        if(a/100==a%10)
        printf("%d正序和逆序相同\n",a);
        else
        printf("%d正序和逆序不同\n",a);
    }



    return 0;
}
 

p3练习2
# include<stdio.h>
# include<stdlib.h>
int main(){
    int year,month,day;

    
    
    printf("请输入年份 月份：\n");
    scanf("%d %d",&year,&month);
    
    if(year<1||month<1||month>12)
    {
        printf("输入数据有误。\n");
        exit(0);
    }
    
    
    if(year%100==0)
    {
        if(year%400==0)
        {if(month==1)
            printf("%d年%d月是31天",year,month);
            else if(month==3)
            printf("%d年%d月是31天",year,month);
            else if(month==5)
            printf("%d年%d月是31天",year,month);
            else if(month==7)
            printf("%d年%d月是31天",year,month);
            else if(month==8)
            printf("%d年%d月是31天",year,month);
            else if(month==10)
            printf("%d年%d月是31天",year,month);
            else if(month==12)
            printf("%d年%d月是31天",year,month);
            else if(month==2)
            printf("%d年%d月是29天",year,month);
            else if(month==4)
            printf("%d年%d月是30天",year,month);
            else if(month==6)
            printf("%d年%d月是30天",year,month);
            else if(month==9)
            printf("%d年%d月是30天",year,month);
            else if(month==11)
            printf("%d年%d月是30天",year,month);
            
        }
        
    }
    else if(year%4==0) 
        {if(month==1)
            printf("%d年%d月是31天",year,month);
            else if(month==3)
            printf("%d年%d月是31天",year,month);
            else if(month==5)
            printf("%d年%d月是31天",year,month);
            else if(month==7)
            printf("%d年%d月是31天",year,month);
            else if(month==8)
            printf("%d年%d月是31天",year,month);
            else if(month==10)
            printf("%d年%d月是31天",year,month);
            else if(month==12)
            printf("%d年%d月是31天",year,month);
            else if(month==2)
            printf("%d年%d月是29天",year,month);
            else if(month==4)
            printf("%d年%d月是30天",year,month);
            else if(month==6)
            printf("%d年%d月是30天",year,month);
            else if(month==9)
            printf("%d年%d月是30天",year,month);
            else if(month==11)
            printf("%d年%d月是30天",year,month);
        } 
    else    if(month==1)
            printf("%d年%d月是31天",year,month);
            else if(month==3)
            printf("%d年%d月是31天",year,month);
            else if(month==5)
            printf("%d年%d月是31天",year,month);
            else if(month==7)
            printf("%d年%d月是31天",year,month);
            else if(month==8)
            printf("%d年%d月是31天",year,month);
            else if(month==10)
            printf("%d年%d月是31天",year,month);
            else if(month==12)
            printf("%d年%d月是31天",year,month);
            else if(month==2)
            printf("%d年%d月是28天",year,month);
            else if(month==4)
            printf("%d年%d月是30天",year,month);
            else if(month==6)
            printf("%d年%d月是30天",year,month);
            else if(month==9)
            printf("%d年%d月是30天",year,month);
            else if(month==11)
            printf("%d年%d月是30天",year,month);
             
             
    return 0;
} 

p3练习3
#include<stdio.h>
int main(){
    int a;
    printf("输入分数（0~100）：");
    scanf("%d",&a);
    
    switch(a/10)
    {
        case 0:
        case 1:
        case 2:
        case 3:
        case 4:
        case 5:printf("不及格\n");break;
        case 6:printf("及格\n");break;
        case 7:printf("中等\n");break;
        case 8:printf("good\n");break;
        case 9:
        case 10:printf("perfect\n");break; 
    }
    return 0;
}