我的作业

#include<stdio.h>
#include<math.h>

int main(void){
       //实验2
    //2.1
    //two.(1) 
    printf("Programming in C is fun!\n");
    printf("学号:2021284101  姓名:毛**  班级:20212841\n");
    printf("你在计算机中心A1机房吗?\n");
    //three 
    //2.2 
    //two.(2) 
    
    int height,g=10,t=3;
    height=g*t*t/2;
    printf("height=%d\n",height);
    //two.(3) 
    int math=87,eng=72,comp=93,average; 
    average=(math+eng+comp)/3;
    printf("math=%d eng=%d comp=%d average=%d\n",math,eng,comp,average);
    //four.(2)
    
    int n=152,digit1,digit2,digit3; 
    digit1=n%10;
    digit2=n/10%10;
    digit3=n/100;
    printf("%d=%d+%d*10+%d*100\n",n,digit1,digit2,digit3);
    //思考： 
    /*
    int n=1234,digit1,digit2,digit3,digit4; 
    digit1=n%10;
    digit2=n/10%10;
    digit3=n/100%10;
    digit4=n/1000;
    printf("%d=%d+%d*10+%d*100+%d*1000\n",n,digit1,digit2,digit3,digit4);*/
    //2.3
    //two.(2)
    //见补充
    //two.(3)
    //见补充
    //three
    //four
    int number,d1,d2,d3;
    printf("Enter number:");
    scanf("%d",&number);
    if(number<100||number>999)
        printf("Invalid Value!");
    else
    {
        
        d1=number%10;
        d2=number/10%10;
        d3=number/100;
        if(number==pow(d1,3)+pow(d2,3)+pow(d3,3))
            printf("Yes");
        else
            printf("No");
    }
  //实验3
    //two(1)
 
    int sign;
    float x;
    printf("Enter x:");scanf("%f",&x);
    
    if(x<0)
        sign=-1;
    else
        if(x==0)
            sign=0;
        else
            sign=1;
    printf("sign(%f)=%d",x,sign);
    
    //two(2)
    /*
    int n1,n2,n3,t; 
    printf("Enter n1,n2,n3:");
    scanf("%d%d%d",&n1,&n2,&n3);
    if(n1>n2)
    {
        t=n1;
        n1=n2;
        n2=t;
    }   
    if(n1>n3)
    {
        t=n1;
        n1=n3;
        n3=t;
    }     
    if(n2>n3)
    {
        t=n2;
        n2=n3;
        n2=t;
    }
    printf("%d->%d->%d\n",n1,n2,n3);
     */
            //three
    /*
    int a,b;
    float cost,zk;
    char c;
    printf("Enter a,b,c:");
    scanf("%d%d %c",&a,&b,&c);
    if(c=='m')
        zk=0.95;
    else if(c=='e')
        zk=0.97;
    else
        printf("输入有误");
    switch(b) 
    {
        case 90:cost=a*6.95*zk;printf("%.2f\n",cost);break;
        case 93:cost=a*7.44*zk;printf("%.2f\n",cost);break;
        case 97:cost=a*7.93*zk;printf("%.2f\n",cost);break;
        default:printf("输入有误");break;
    }*/
           ///////////////////////补充////////////////////////////////////
           // 实验2
            //2.3
    //two.(2)
    /*
    int year;
    float money,rate,interest;
    printf("Enter money,year,rate:");
    scanf("%f%d%f",&money,&year,&rate);
    interest=money*pow((1+rate),year)-money;
    printf("interest=%.2f\n",interest);*/
    //two.(3)
    
    float f,x;
    printf("Enter x:");
    scanf("%f",&x);
    f=(x<0)?pow((x+1),2)+2*x+1/x:sqrt(x);
    //if(x<0) f=pow((x+1),2)+2*x+1/x;
    //else f=sqrt(x);
    printf("f(%.2f)=%.2f\n",x,f);
    
    //fout
    //(1)
/*
    float cost,e;
    printf("Enter e:");
    scanf("%f",&e); 
    if(e>=0)
    {
        if(e<=50)
            cost=e*0.53;
        else
            cost=50*0.53+(e-50)*0.58;
        printf("cost=%.2f",cost);
    }
    else
    {
        printf("Invalid Value!");
    }*/
    
    //(2)
/*
    int time1,time2,h,min;
    printf("Enter time1:");
    scanf("%d",&time1); 
    printf("Enter time2:");
    scanf("%d",&time2); 
    min=time2%100-time1%100;
    h=time2/100-time1/100;
    if(min<0)
    {
        min=min+60;
        --h;
    }
    printf("%02d%02d",h,min);*/
    //实验3   
    //two.(4)   
    
    /*
    float apple=3.00,pear=2.50,orange=4.10,grape=10.20;
    printf("[1]apple\n[2]pear\n[3]orange\n[4]grape\n[0]exit\n");
    int choice,i=0;
    printf("Enter choice:");    
    do 
    {
        scanf("%d",&choice);    
        ++i;
        switch(choice)
        {
            
            case 1:
                printf("price=%.1f\n",apple);break;
            case 2:
                printf("price=%.1f\n",pear);break;
            case 3:
                printf("price=%.1f\n",orange);break;
            case 4:
                printf("price=%.1f\n",grape);break;
            case 0:
                break;
            default:
                printf("price=0\n");break;
            }
    }while(i<5);*/
    
//four.{1)  
/*
    int n;
    printf("Enter n:");
    scanf("%d",&n); 
    switch(n%5)
    {
        case 0:case 4:printf("Drying in day %d\n",n);break;
        case 1:case 2:case 3: printf("Fishing in day %d\n",n);break;
    }*/ 
    
    
//four.{1)
/*
    float a,b,c,t,x1,x2,p,q;
    printf("Enter a,b,c:");
    scanf("%f%f%f",&a,&b,&c);
    if(a==0)
    {
        if(c==0&&b==0)
            printf("Zero Equation");
        else if(b!=0)
            printf("%.2f",-(c/b));
        else
            printf("Not An Equation");
    }
    else
    {
        t=b*b-4*a*c;
        if(t>0)
        {
            x1=(-b+sqrt(t))/(2*a);
            x2=(-b-sqrt(t))/(2*a);
            printf("%.2f\n%.2f",x1,x2);
        }else if(t==0)
        {
            x1=(-b+sqrt(t))/(2*a);
            printf("%.2f",x1);
        }else
        {
            p=(-b)/(2*a);
            q=sqrt(-t)/(2*a);
            printf("%.2f+%.2fi\n%.2f-%.2fi",p,q,p,q);
            
        }
    }*/

return 0;

}