Question

编写C语言程序，输入圆的半径，求出圆的周长和面积并输出

Answer 1

#include <stdio.h>void main()
{
float r;
printf("请输入圆的半径: ");
scanf("%f",&r);
printf("圆的周长是: %f\n",(2*3.14*r));//求出圆周长
printf("圆的面积是: %f\n",(3.14*r*r));//求出圆面积
}

Answer 2

#include <stdio.h>
void main()
{
float h,r,l,s,PI=3.141526;;
printf("请输入圆半径r,圆柱高h:");
scanf("%f,%f",&r,&h);
l=PI*(r*2);
s=(r*r)*PI;
printf("圆的周长:%6.2f\n",l);
printf("圆的面积:%6.2f\n",s);}

Answer 3

#include<stdio.h>#define PI 3.1415#define P printf#define S scanfvoid main(){float r,s,c;P("输入半径r\n");S("%f",&r);s=PI*r*r;c=2*PI*r;P("s=%5.2f,c=%5.2f",s,c);}

Answer 4

#include <stdio.h>
#define PI 3.14
void main()
{
int r;
float s,c;
printf("please input r\n");
scanf("%d",&r);
s=r*r*PI;
c=r*2*PI;
printf("zhouchang = %f,mianji =%f",c,s);
}

Answer 5

#define PI3.1416
void main()
{
float r,c,s;
scanf("%d",&r);
c=2*PI*r
s=PI*r*r
printf("c=%6.2f,s=%6.2f\n",c,s);
}