编写一个求圆面积的函数Area,

#include#definePI3.1415926doublearea(doubler){returnPI*r*r;}doubleperimeter(doubler){return2*PI*r;}i

#include#includeusingnamespacestd;classRectangle:publicShape{floatx1,x2,y1,y2;public:Rectangle(float

#definePI3.14#includeusingnamespacestd;doublearea(floati){return(PI*i*i);}doublecircumference(floati

第一个空,函数需要返回一个double类型的值,因此填：returna;第二个空,需要对a=5用area函数,因此填：area(a)最后这是一个C语言的问题,如果在计算机分类上问应该很快就解决了吧.

函数定义名Area,参数rFunctionArea(r)Area=3.1415926*r*rEndFunction调用例子：PrivateSubCommand1_Click()Label1.Capti

什么语言?给你个C#的,根据你需要的语言,改动一下privatedoublemiji(doublebanjing){doublepi=3.14;returnpi*banjing*banjing;}再问

#include<stdio.h>#include<stdlib.h>#define Pi 3.14159double square(double

classTrapezoid:publicShape{private:\x05doubletop;\x05doublebottom;\x05doubleheight;public:\x05Trapez

classTrapezoid:publicShape{private:doubletop;doublebottom;doubleheight;public:Trapezoid(doublet,

#include <stdio.h>float area(float r){  return 3.14159 *&nb

#include<stdio.h>#define Pi 3.14159double Square(double r){  &nb

include#include#defineS(a+b+c)/2#defineAREA(a,b,c)sqrt(S*(S-a)*(S-b)*(S-c))main(){floata,b,c;printf(

p=1/4*(2*x*z+y*y-x*x-z*z);应该改为p=1.0/4*(2*x*z+y*y-x*x-z*z);或者p=1/4.0*(2*x*z+y*y-x*x-z*z);原因是：当进行运算时,1

Console.WriteLine("请输入圆的半径");intr=int.Parse(Console.ReadLine());doublecircle=2*3.14*r;doublearea=3.1

1.functions=mianji(r)s=pi*r*r;end2.functionl=zhouchang(r)l=2*pi*r;end

voids(folata,folatb,folatc){folatp;p=(a+b+c)/2;S=√[p(p-a)(p-b)(p-c)];returns;}

publicinterfaceCircle{doublearea(doubler);}publicclassCircleImplimplementsCircle{publicdoublearea(do

//使用海伦公式#include/*ForIO*/#include/*Forsqrt()*/intmain(void){doublea,b,c,p,s;printf("请输入a,b和c：");scan

functionfun(d,h){if(d

利用海伦公式：S=(p(p-a)(p-b)(p-c))^(1/2);S为三角形面积,a,b,c为三角形三边长,p为三角形半周长（p=（a+b+c)*(1/2))(p(p-a)(p-b)(p-c))^(