Printing variables with member function does not give correct values

Question

Running the program will take user input and validate, but does not print the expected information. I can simply enter 5 for each dimension and 'blue' for color but then receive:

The length is: 2.97299e-41
The width is: 2.99205e-41
The height is: 2.99205e-41
The color is: 
The volume is: 0

Could someone please explain why the input info does not carry to the print stage? Here is the code:

#include <iostream>
#include <string>
using namespace std;
// User is prompted for cube dimensions and color, which is validated. Create class Cube,          calculate volume,
// then display the stored information from Cube.
string length;  // declare variables
string width;
string height;
string volume;
string color;

int main() {
    int flag = 0;                       // flag, duh
    cout << "Enter the cube length: ";  // user input dimensions & color
    cin >> length;
    for (int i = 0; i < length.size(); i++)  // input validation for integers
    {
        if (!isdigit(length[i])) {
            flag = 1;
            break;
        }
    }
    if (flag == 1) cout << "Enter a valid number." << endl;
    cout << "Enter the cube length: ";
    cin >> length;

    cout << "Enter the cube width: ";
    cin >> width;
    for (int i = 0; i < width.size(); i++) {
        if (!isdigit(width[i])) {
            flag = 1;
            break;
        }
    }
    if (flag == 1) cout << "Enter a valid number." << endl;
    cout << "Enter the cube width: ";
    cin >> width;

    cout << "Enter the cube height: ";
    cin >> height;
    for (int i = 0; i < height.size(); i++) {
        if (!isdigit(height[i])) {
            flag = 1;
            break;
        }
    }
    if (flag == 1) cout << "Enter a valid number." << endl;
    cout << "Enter the cube height: ";
    cin >> height;

    cout << "Enter the cube color: ";
    cin >> color;
    for (int i = 0; i < color.size(); i++)  // input validation for string
    {
        if (flag == 1) cout << "Enter a valid color." << endl;
        cout << "Enter the cube color: ";
        cin >> color;

        if (!isdigit(color[i])) {
            flag = 1;
            break;
        }
    }
    stof(length);  // string values convert to integer
    stof(width);
    stof(height);

    Cube access;       // create object
    access.display();  // call member function
}
class Cube {
public:
    float length;
    float width;
    float height;
    float volume = length * width * height;  // calculate volume
    string color;
    void display() {  // display Cube information
        cout << "The length is: " << length << endl;
        cout << "The width is: " << width << endl;
        cout << "The height is: " << height << endl;
        cout << "The color is: " << color << endl;
        cout << "The volume is: " << volume << endl;
    }
};

I tried providing different values, but none go through. Using the input example mentioned above code, I expect:

The length is: 5
The width is: 5
The height is: 5
The color is: blue
The volume is: 125

Answer 1

I solve your question adding a function to calculate the volume and using the variables inside the object.

#include <iostream>
#include <string>
using namespace std;

string length;
string width;
string height;
string volume;
string color;

class Cube
{
public:
    float length;
    float width;
    float height;
    float volume;
    string color;
    void display()
    {
        cout << "The length is: " << length << endl;
        cout << "The width is: " << width << endl;
        cout << "The height is: " << height << endl;
        cout << "The color is: " << color << endl;
        cout << "The volume is: " << volume << endl;
    }
    void calculateVolume()
    {
        volume = length * width * height;
    }
};

int main()
{
    int flag = 0;
    cout << "Enter the cube length: ";
    cin >> length;
    for (int i = 0; i < length.size(); i++)
    {
        if (!isdigit(length[i]))
        {
            flag = 1;
            break;
        }
    }
    if (flag == 1)
        cout << "Enter a valid number." << endl;

    cout << "Enter the cube width: ";
    cin >> width;
    for (int i = 0; i < width.size(); i++)
    {
        if (!isdigit(width[i]))
        {
            flag = 1;
            break;
        }
    }
    if (flag == 1)
        cout << "Enter a valid number." << endl;

    cout << "Enter the cube height: ";
    cin >> height;
    for (int i = 0; i < height.size(); i++)
    {
        if (!isdigit(height[i]))
        {
            flag = 1;
            break;
        }
    }
    if (flag == 1)
        cout << "Enter a valid number." << endl;

    cout << "Enter the cube color: ";
    cin >> color;
    for (int i = 0; i < color.size(); i++)
    {
        if (flag == 1)
            cout << "Enter a valid color." << endl;

        if (!isdigit(color[i]))
        {
            flag = 1;
            break;
        }
    }

    Cube access;
    access.length = stof(length);
    access.width = stof(width);
    access.height = stof(height);
    access.color = color;
    access.calculateVolume();
    access.display();
}