#include <stdio.h>
#include <string.h>
#include <math.h>

double calculateAera();
double calculatePaint();
double calculatePaintRounded();

void main() {
	double totalArea = 0;

	//Calculate Wall Area
	int moreWalls = 1;
	double height = 0, width = 0;
	char moreWall[50];
	while (moreWalls == 1) {
		printf("Enter Wall Height (m): ");
		scanf("%lf", &height);

		printf("\nEnter Wall Width (m): ");
		scanf("%lf", &width);
		totalArea += calculateAera(height, width);

		printf("\nMore Walls? (y/n):");
		scanf("%s", moreWall);
		if (moreWall[0] == 110) {
			moreWalls = 0;
		}
		printf("\n");
	}

	printf("\nTotal Wall Area = %lf", totalArea);

	//Calculate Door Area
	int doorAmmount = 0;
	printf("\nHow many doors are there in the room? (count a double door as 2): ");
	scanf("%d", &doorAmmount);
	totalArea -= 2.5 * doorAmmount;
	printf("\nTotal Wall Area = %lf", totalArea);

	//Calculate Widnow Area
	int anyWindows = 1;
	char anyWindow[50];

	double windowHeight = 0, windowWidth = 0;
	printf("\nAny windows (y/n)?: ");
	scanf("%s", anyWindow);

	if (anyWindow[0] == 110) {
		anyWindows = 0;
	}
	while (anyWindows == 1) {
		printf("Enter Wall Height (m): ");
		scanf("%lf", &windowHeight);

		printf("\nEnter Wall Width (m): ");
		scanf("%lf", &windowWidth);
		totalArea -= calculateAera(windowHeight, windowWidth);

		printf("\nAny more windows (y/n)?: ");
		scanf("%s", anyWindow);
		if (anyWindow[0] == 110) {
			anyWindows = 0;
		}
	}
	printf("\nTotal Wall Area = %lf", totalArea);

	//Calculate Paint
	double paintCoverage = 0;
	printf("\nWhat is the coverage in m2 per liter of your paint?: ");
	scanf("%lf", &paintCoverage);

	int coatAmmount = 0;
	printf("\nHow many coats do you want?: ");
	scanf("%d", &coatAmmount);

	double paintAmmount = calculatePaint(totalArea, coatAmmount, paintCoverage);
	printf("\nYou will need %lf or %lf to the nearest litre of paint", paintAmmount, round(paintAmmount));

}

double calculateAera(double height, double width) {
	return(height * width);
};
double calculatePaint(double area, int numCoats, double m2PerLitre) {
	return(area / (m2PerLitre / numCoats));
};