C++ Variable help

[lotsofsloths]

Ok so here is my code for a practice homework at LiduidEmberS

#include <iostream>
using namespace std;
int main(void)
{
    int a;
    int b;
    int c;
    int d;
    int radius;
    int volumeprism;
    volumeprism = b*c*d;
    int volumesphere = 1.3333333333333*3.1415926536*(radius^3);


    cout << "Welcome to the program!\n\n";
    cout << "Do you want the volume of:\n";
    cout << "1. Cube\n";
    cout << "2. Sphere\n";
    cout << "3. Exit\n";
    cin >> a;
    switch (a)
    {
    case 1:
        cout<<"enter length";
        cin >> b;
        cout<<"enter height";
        cin >> c;
        cout<<"enter width";
        cin >> d;
        cout << volumeprism;
    break;

    case 2:
        cout << "enter radius";
        cin >> radius;
        cout << volumesphere;
    break;

    case 3:
        return 0;
    break;
    }
    
    return 0;
}

...
I always get the following Warnings:
c:\documents and settings\family\my documents\visual studio 2005\projects\homework1volume\homework1volume\the code.cpp(12) : warning C4244: 'initializing' : conversion from 'double' to 'int', possible loss of data
c:\documents and settings\family\my documents\visual studio 2005\projects\homework1volume\homework1volume\the code.cpp(11) : warning C4700: uninitialized local variable 'b' used
c:\documents and settings\family\my documents\visual studio 2005\projects\homework1volume\homework1volume\the code.cpp(11) : warning C4700: uninitialized local variable 'c' used
c:\documents and settings\family\my documents\visual studio 2005\projects\homework1volume\homework1volume\the code.cpp(11) : warning C4700: uninitialized local variable 'd' used
c:\documents and settings\family\my documents\visual studio 2005\projects\homework1volume\homework1volume\the code.cpp(12) : warning C4700: uninitialized local variable 'radius' used
So by now i KNOW that its something wrong with the variables and the math....
Please help me fix this problem..!

[Sturm]

you did not initialize a, b, c, d, and radius. Get the input than assign.

[ndeniche]

first of all, the first warning (the one that says about double and int) means that you are initializin an integer (whole number) with values of a double number (a number with decimal points and extreme accuracy)... so, you should initialize your variable as a float or double...

[ndeniche]

yup, you should give values to a,b, c and radius before using them in a mathematic operation...

int a;//you
int b;//are
int c;//not
int radius;//giving any values to these variables
int volumeprism;
volumeprism=a*b*c; //so when you use them here, 
//it will give you random numbers,
//or what we call junk

got it?

[lotsofsloths]

Umm...not really, explain lol

[ndeniche]

ok... look...

when you initialize a variable with no values, this variables has a random value stored in it. in your program, you assign values to your variables until the end, where you have your switch...

what you have to do is the following:

#include <iostream>
using namespace std;
int main(void)
{
    int a,b,c,d,radius,volumeprism;//see how you can declare
                                   //several variables at the
                                   //same time
    double volumesphere;//volumesphere must be declared as a
                        //double so it returns decimal values

    cout << "Welcome to the program!\n\n";
    cout << "Do you want the volume of:\n";
    cout << "1. Cube\n";
    cout << "2. Sphere\n";
    cout << "3. Exit\n";
    cin >> a;
    switch (a)
    {
    case 1:
        cout<<"enter length";
        cin >> b;
        cout<<"enter height";
        cin >> c;
        cout<<"enter width";
        cin >> d;
        volumeprism=b*c*d;//the math operation you had @ the
                          //beginning goes here so it multiplies
                          //the values you want it to multiply
        cout << volumeprism;
    break;

    case 2:
        cout << "enter radius";
        cin >> radius;
        volumesphere=1.333333333333*3.1415926536*(radius^3);

        //here's the other math operation you had up there

        cout << volumesphere;
    break;

    case 3:
        return 0;
    break;
    }
    
    return 0;
}

and that should do the trick...

the problem is you thought a mathematical operation done in a variable would be done every time you gave different values to variables...

well... that doesn't happen in c++ (or even any other languages)...

[lotsofsloths]

Ahh..
ur a good explainer u know?

[ndeniche]

thank you very much...

solving problems @ daniweb has made me improve my explaining abilities... :D

remember marking your thread as solved if your problem was solved...