/*  miles/gallon  to liters/100 kilometers (10 points)

Write a complete C program that converts the fuel consumption of a vehicle
from miles per gallon to liters per 100 kilometers.
The program must do the following:
  * ask the user to enter a number representing the miles/gallon
  * calculate the conversion and print the result on the screen

Hint:   1 kilometer = 0.621 miles
		1 gallon = 3.785 liters
		
Example:

This program converts miles/gallon to liters/100 kilometers
Enter a value (miles/gallon): 50

 50.000000 miles/gallon = 4.700970 liters/100 kilometers

*/ 

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

#define KILOMETERS_PER_MILE (1.0/0.621)
#define LITERS_PER_GALLON 3.785

int main(void)
{
    
	double mpg; // miles per gallon
	double kmg; // kilometers per gallon
	double kml; // kilometers per liter
	double lp100km; // liters per 100 kilometers
	    
    printf("This program converts miles/gallon to liters/100 kilometers\n"); 
	printf("Enter a value (miles/gallon): ");
	
    scanf("%lf", &mpg);
    
    kmg = mpg * KILOMETERS_PER_MILE; // convert to kilometers per galon
    
    kml = kmg / LITERS_PER_GALLON; // convert to kilometers per liter
    
    lp100km = 100/kml;
    
    
    printf("\n %lf miles/gallon = %lf liters/100 kilometers \n\n", mpg, lp100km);
    
    system("pause");
}