#include <iostream>
#include <time.h>
#include <vector>

//void menuDisp();
double circum(double);

using namespace std;
int main(){
    
    //srand(time(NULL));
    //int x= (rand()%5)+1;
    //cout << x;
    
    //menuDisp();
    
    double rad=0;
    double circumference=0;
    cout << "\nEnter a value for the radius: ";
    cin >> rad;
    
    circumference = circum(rad);
    cout << "\n The circumference of the circle is: " << circumference << endl;
    
    
return 0;
}

//void menuDisp(){
//    std::cout << "\nWelcome to the tutorial, press 1 for bacon: ";
//}

double circum (double radius){
    double pi = 3.1415;
    double circumf =(2*radius)* pi;
    return circumf;
}