Functions Help - ASAP PLEASE

[darkslayer3]

I'm trying to create a program that uses functions to determine the length, width then the final area of something but having some trouble. I run into the value being 0 in the end and not sure what I'm doing wrong! I have to assign the value 0 to the doubles as you will see but if I do not assign 0 it also doesn't run the program and states they are undeclared and it's quite frustrating I've tried everything, please point out my errors?

#include <iostream>
using namespace std;

double getLength(double length);
double getWidth(double width);
double getArea(double area, double length, double width);
void displayData(double length, double width, double area);

int main() {
	double length = 0;
	double width = 0;
	double area = 0;
	getLength(length);
	getWidth(width);
	getArea(area, length, width);
	displayData(length, width, area);
	return 0;
}
double getLength(double length) 
{
	cout << "Please enter the length\n";
	cin >> length;
	return length;
}
double getWidth(double width)
{
	cout << "Please enter the width\n";
	cin >> width;
	return width;
}
void displayData(double length, double width, double area) {
	cout << "Area: " << area << endl;
}
double getArea(double area, double length, double width)
{
	area = length * width;
	return area;
}

[SamuelAdams]

Your using the same names (length, width, area) in main as you are in your functions. It should work but it's going to be confusing to debug.

[EtDecius]

I see two issues:

1) Your functions return a value, but that value is not stored anywhere. Try to store the returned value in a variable.

length = getLength();
width = getWidth();
area = getArea(length, width);

2) Since the functions getLength() and getWidth() ask the user for the data, you don't need to pass any arguments. The functions can be updated as:

double getLength();
double getWidth();

Similarly, the arguments for getArea() and displayData() should be limited only to values those functions use. No need to pass extra data that the function doesn't utilize.