第三次作业

1.编程打印10行的三角形，要求每行显示的*号个数等于行数；

#include<stdio.h>
int main ()
{
    printf ("*
");
    printf ("**
");
    printf ("***
");
    printf ("****
");
    printf ("*****
");
    printf ("******
");
    printf ("*******
");
    printf ("********
");
    printf ("*********
");
    printf ("**********");
}

2.编程打印10行*号，每行打印10个*号

#include<stdio.h>
int main(void)
{
    printf("**********
");
    printf("**********
");
    printf("**********
");
    printf("**********
");
    printf("**********
");
    printf("**********
");
    printf("**********
");
    printf("**********
");
    printf("**********
");
    printf("**********
");
}

3.

#include<stdio.h>
int main(void)
{   printf("**********
");    
    printf("*********
");
    printf("********
");
    printf("*******
");
    printf("******
");
    printf("*****
");
    printf("****
");
    printf("***
");
    printf("**
");
    printf("*
");
}

 4.

#include<stdio.h>
int main()
{
char score;
scanf("%c",&score);
switch (score)
{
case 'A':
printf("100~90");
break;

case 'B':
printf("89~80");
break;

case 'C':
printf("79~70");
break;

case 'D':
printf("69~60");
break;

case 'E':
printf("59~0");
break;

default:
printf("输入有误");
break; }
return 0;
}

5.

#include<stdio.h>
int main()//计算华氏温度100°F对应的摄氏温度
{
    int F=100;
    int C;
    printf("C=%d",C=5*(F-32)/9);
    return 0;
}

6.

#include<stdio.h>
int main()//计算华氏温度100°F对应的摄氏温度
{
    int t=3;
    int a=10;
    int s;
    printf("s=%d",s=0.5*a*t*t);
    return 0;
}

7.

#include<stdio.h>
int main()
{
    int a=152;
    int b;
    int c;
    int d;
    b=a%10;
    c=(a%100-b)*0.1;
    d=a/100 ;
    printf("个位数=%d
",b);

    printf("十位数=%d
",c); 

    printf("百位数=%d
",d); 

return 0; }

8.

#include<stdio.h>
#include<math.h>
int main()
{
    double x;
    double y;
    scanf("%lf",&x);
    if(x>=0)
       y=sqrt(x);
    else 
       y=pow(x+1,2)+2*x+1/x;
    printf("f(x)=%f",y);
    return 0;
}

9.

#include<stdio.h>
#include<math.h>
int main()
{
   int money,year;
    double rate,interest;
    printf("请分别输入存款金额、存期、年利率: ");
    scanf("%d %d %lf",&money,&year,&rate );
   interest=money*pow(1+rate,year)-money;
    printf("interest=%f
",interest);
    return 0;}

10

#include<stdio.h>
int main()
{
   int a;
   double b;
   scanf ("%d",&a);
   if(a<=50)
   {b=a*0.53;}
   else
   {b=50*0.53+(a-50)*0.05;}
   printf ("%lf",b);
   }