c语言编程练习题

第一个是输入半径，输出圆的直径、周长、面积
const double p = 3.14159;
void main()
{
double radius = 0;
printf("Radius of Circle:");
scanf("%lf", &radius);

printf("Diameter:%lf, Circumference:%lf, Area:%f ", 2*radius, 2*p*radius, p*radius*radius);
}

第二个是根据给定的余额和利息，计算一年以后的余额
void main()
{
double initBalance = 6000;
double interestRate = 0.0425;
printf("Interestcalculation program.\nStarting balance:%.lf Annual\ninterest rate percentage:%.4lf\n", initBalance,interestRate);
printf("One year balance:%.lf", initBalance*(1+interestRate));
}

翻译为
编写程序，读取一个圆的半径和打印该圆的直径，周长和面积。使用值3.14159为“P”。写一个程序：承担起平衡6000年利率为4.25%。你的程序应该显示一年后的新的平衡。没有存款或退出–只是利息支付。你的程序应该能够重现以下samplerun：interestcalculation程序。startingbalance？6000annualinterest率？4.25balanceafter一年：6255

#include
using namespace std;
const float pi=3.14;
void circle(float);
int main()
{
float R;
cout<<"please input the radius of a circle: ";
cin>>R;
circle(R);
return 0;
}
void circle(float r)
{
float dia,circumference,area;
dia=2*r;
cout<<"the diameter is :"< circumference=dia*pi;
cout<<"the circumference is :"< area=pi*r*r;
cout<<"the area is :"<
}

一楼的回答是固定的利率啊？应该由程序运行时输入的利率来计算才对的啊？
program First:
main()
{
float p=3.14159;
float r,d,l,s;
printf("r=");
scanf("%f",&r);
d=2*r;
l=2*p*r;
s=p*r*r;
printf("d=%4.2f l=%4.2f s=%4.2f\n",d,l,s);
getch();
}

program second:
main()
{
float a,p;
printf("Starting balance?");
scanf("%f",&a);
printf("Interest rate percentage?");
scanf("%f",&p);
a*=(1+p/100);
printf("Balance after one year: %4.0f\n",a);
getch();
}

呵呵，你在国外读书啊？题目竟然是用英文出的，不过看起来挺简单的啊

#include "stdafx.h"
#include
using namespace std;

int main()
{
float r ,d,c,a;
float p = 3.14159;

r = -1;
while ( r <= 0)
{
cout<<"Please input the radius of a circle :"< cin>>r;

if(r <= 0)
cout<<"The radius should be over than 0 !"< }

d = 2.0 * r;
c = d * p;
a = p * r * r;

cout<<"The diameter is :"<< d < cout<<"The circumference is :"<< c < cout<<"The area is :"<< a < system("pause");
return 0;
}