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

float radius;//Radius of each cylinder
float height;//Height of each cylinder
float computeVolume (float, float);//Function prototype

int main () //Main function:

{
    int numCylinders;//Problem Inputs: Number of cylinders
	int counter;//Problem variables: Counter
	
	
	float volume;//Volume of each cylinder
	float totalVolume;
	totalVolume = 0;
	float average;
	
	//Get the number of cylinders
	cout << "How many cylinders would you like to calculate the volume of? ";
	cin >> numCylinders;
	for (counter = 0; counter < numCylinders; counter++)
	{
		//Get the radius and height of each cylinder
		cout << "Enter the radius of the cylinder: ";
		cin >> radius;
		cout << "Enter the height of the cylinder: ";
		cin >> height;
		computeVolume (radius, height);//Call function volume
		cout << "The volume of a cylinder with radius " << radius << " and height " << height << " is " << volume << endl;//Display volume
		totalVolume += volume;//Add volume to total volume
	}
	if (numCylinders != 0)
	{
		cout << "The total volume of all cylinders is " << totalVolume << endl;//Output the total volume
		average = totalVolume / numCylinders;//Compute the average volume
		cout << "The average volume of all cylinders is " << average;//Display the average volume
	}
	else
		cout << "Invalid number.  Please try again." << endl;//Display warning

	return 0;
}
float computeVolume (float thisRadius, float thisHeight)//Volume function

{
	float thisVolume;//local variable
	
	float const PI = 3.14159;//Problem constant
	thisVolume = ((PI * (pow (thisRadius, 2))) * thisHeight);//Calculate volume of each cylinder
	return thisVolume;
}

computeVolume (radius, height);//Call function volume

volume = computeVolume (radius, height);//Call function volume