BMI Calculator with functions

[alwaystiredman]

So the program runs, but it always spits out 0 for the bmi and I can't figure out why. Help is greatly appreciated!

#include <iostream>
#include<iomanip>
#include<cmath>
using namespace std;

double calculateBMI (double weight, double height)
{
double bmi= (weight * 703)/(height * height);
return bmi;
}

void displayHealthStatus (double bmi)
{
cout << "Your BMI value is " << bmi <<
"\n\nBMI VALUES \n underweight: less than 18.5"<<
"\n Normal: between 18.5 and 24.9"<<
"\n Overweight: between 25 and 29.9"<<
"\n Obese: 30 or greater" << endl;
}

int main()
{
double weight, height, bmi;

cout << "Enter your weight in pounds: ";
cin >> weight;
cout << "Enter your height in inches: ";
cin >> height;

calculateBMI(height, weight);
//BMI always comes out to zero and I don't know why
displayHealthStatus(bmi);

return 0;
}

[TheIdeasMan]

You didn't assign the value returned from calculateBMI to anything :+)

Pleas always use code tags: http://www.cplusplus.com/articles/z13hAqkS/

Always initialise your variables to something, preferably wait until you have a sensible value to assign to it, otherwise at the same time as declaration:

double weight = 0.0;
double  height = 0.0;

// ...

double bmi = calculateBMI(height, weight);

Do 1 variable declaration per line.

Put forward declarations of the functions before main, function definitions after main. This is so main is near the top of the file.

[chicofeo]

A couple of options.
You have the height and weight parameters swapped.

Option A.
This calculateBMI(height, weight); , should be this bmi = calculateBMI(weight, height);

OR

Option B.
From this...

calculateBMI(height, weight);
//BMI always comes out to zero and I don't know why
displayHealthStatus(bmi);

TO
displayHealthStatus(calculateBMI(weight, height));

The reason is that the function calculateBMI returns the BMI value back to the calling function.

Your choice.

[alwaystiredman]

Thanks guys! Everything works perfectly now