5
❖The first C++ program in two versions
// Circle1.cpp
#include "cstdio"
#include "cmath"
using namespace std;
int main()
{
const double pi = 3.14159265359;
double radius, area, perimeter;
// Reading radius
printf("Radius = ");
scanf("%lf", &radius);
// Calculations
perimeter = 2 * radius*pi;
area = pow(radius, 2)*pi;
printf("Perimeter: %7.3f\n",
perimeter);
printf("Area: %7.3f\n", area);
// Waiting for pressing Enter
getchar();
getchar();
return 0;
}
// Circle2.cpp
#include "iostream"
#include "cmath"
using namespace std;
int main()
{
const double pi = 3.14159265359;
// Reading radius
double radius;
cout << "Radius = ";
cin >> radius;
// Calculations
double perimeter = 2 * radius*pi;
double area = pow(radius, 2)*pi;
cout << "Perimeter: " << perimeter <<
endl;
cout << "Area: " << area << endl;
// Waiting for pressing Enter
cin.get();
cin.get();
return 0;
}
C C++
1. Creation of C++ programs