Problem with my program

owemeacent (10)
I recently made a program which calculates pi formulas and I'm having trouble calculating the volume of a cone, every time it receives input, it still print out a zero. Is there any way I could solve this?

And as a side question, is there anything I could do to make it faster?

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  (#include "stdafx.h"
#include <iostream>
#include <cmath>
using namespace std;
int main();
void chooser();

const double pi = 3.14159;


void circleCircum()
{
  char choose;
  do
  {
    cout <<  "Enter radius" <<  endl;
    int radius = 0;
    cin >> radius;
    int circum = pi * ( 2 * radius);
    cout <<  "Circumference is: " <<  circum <<  endl;
    cout <<  "Do you want to do this again? (y/n)" <<  endl;
    
    cin >> choose;
  }while (choose ==  'y');
  chooser();
}


void surfaceCylinder()
{
  char choose;
  do
  {
    cout << "Enter radius" <<  endl;
    int radius = 0;
    cin >> radius;
    cout <<  "Enter height" <<  endl;
    int height = 0;
    cin >> height;
    int surface = (2 * pi * (radius * radius)) + (2 * pi * radius * height);
    cout << "Surface Area is:" <<  surface <<  endl;
    cout <<  "Do you want to do this again? (y/n)" <<  endl;
    
    cin >> choose;
  }while (choose ==  'y');
  chooser();
    
}

void volumeCylinder()
{
  char choose;
  do
  {
    cout <<  "Enter radius" <<  endl;
    int radius = 0;
    cin >> radius;
    cout <<  "Enter height" <<  endl;
    int height = 0;
    cin >> height;
    int volume = pi * (radius * radius) * height;
    cout <<  "Volume is: " <<  volume <<  endl;
    cout <<  "Do you want to do this again? (y/n)" <<  endl;
    
    cin >> choose;
  }while (choose ==  'y');
  chooser();
}


    
void surfaceCone()
{
  char choose;
  do
  {
    cout <<  "Enter radius" <<  endl;
    int radius = 0;
    cin >> radius;
    cout <<  "Enter slope" <<  endl;
    int slope = 0;
	cin >> slope;
    int surface = (pi * radius * slope) + (pi * (radius * radius));
    cout <<  "Surface Area is:" <<  surface <<  endl;
    cout <<  "Do you want to do this again? (y/n)" <<  endl;
    
    cin >> choose;
  }while (choose ==  'y');
  chooser();
}

void volumeCone()
{
  char choose;
  do
  {
    cout <<  "Enter radius" <<  endl;
    int radius = 0;
    cin >> radius;
    cout <<  "Enter height" <<  endl;
    int height = 0;
    cin >> height; 
    int volume = (1/3) * pi * (radius * radius) * height;
    cout <<  "Volume is:" << volume <<  endl;
    cout <<  "Do you want to do this again? (y/n)" <<  endl;
    
    cin >> choose;
  }while (choose ==  'y');
  chooser();
}














void chooser()
{
  cout <<  "Command characters: " <<  endl;
  cout <<  "Circumference of a circle: c" <<  endl <<  "Surface Area of a cylinder: s" <<  endl <<  "Volume of a cylinder: v" <<  endl <<  "Surface Area of a cone: u" <<  endl;
  cout <<  "Volume of a cone: o" <<  endl << "Exit program: x" <<  endl;
  char choose;
  cin >> choose;
  
  switch (choose)
  {
    case 'c':
      circleCircum();
      break;
    
    case 's':
      surfaceCylinder();
      break;
    
    case 'v':
      volumeCylinder();
      break;
    
    case 'u':
      surfaceCone();
      break;
    
    case 'o':
      volumeCone();
      break;
    
    case 'x':
    return;
      break;
    
    
    
    default:
      cout <<  "You did not enter a valid charcter" <<  endl;
      chooser();
      break;
  }
}
  

int main()
{
cout <<  "Hello, this is the Pi equations calculator alpha 0.3" <<  endl;
chooser();
cout <<  "Bye" <<  endl;
return 0;
}
ats15 (423)
The problem is that you are using ints, when you should use floats or doubles. For ints 1/3=0
owemeacent (10)
I tried that and it didn't work
ats15 (423)
Check if you get the same answer. Igore the static_cast, I just did that to suppress a warning. Note how I wrote 1/3 as 1./3., and all variables are doubles, not ints
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#include<iostream>
using namespace std;

const double pi = 3.14159;

int main()
{
int volume,radius=1,height=1;
volume = static_cast<int>((1/3) * pi * (radius * radius) * height);
cout<<volume<<endl;

double dvolume,dradius=1.,dheight=1.;
dvolume = (1./3.) * pi * (dradius * dradius) * dheight;
cout<<dvolume<<endl;
}
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