// This program computes two people's body mass index (BMI) and compares them.
// This version also uses more parameters and return values.

import java.util.*;  // so that I can use Scanner

public class BMI {
    public static void main(String[] args) {
        introduction();
        Scanner console = new Scanner(System.in);
        processTwoPeople(console);
    }
    
    // optional method to process two people.
    public static void processTwoPeople(Scanner console) {
        double bmi1 = processPerson(console);
        double bmi2 = processPerson(console);
        
        // report overall results
        System.out.println("Person #1 body mass index = " + bmi1);
        System.out.println("Person #2 body mass index = " + bmi2);
        double difference = Math.abs(bmi1 - bmi2);
        System.out.println("Difference = " + difference);
    }
    
    // prints a welcome message explaining the program
    public static void introduction() {
        System.out.println("This program reads in data for two people");
        System.out.println("and computes their body mass index (BMI)");
        System.out.println("and weight status.");
        System.out.println();
    }
    
    // reads information for one person, computes their BMI, and returns it
    public static double processPerson(Scanner console) {
        System.out.println("Enter next person's information:");
        System.out.print("height (in inches)? ");
        double height = console.nextDouble();
        
        System.out.print("weight (in pounds)? ");
        double weight = console.nextDouble();
        System.out.println();
        
        double bmi = getBMI(height, weight);
        return bmi;
    }
    
    // Computes a person's body mass index based on their height and weight
    // and returns the BMI as its result.
    public static double getBMI(double height, double weight) {
        double bmi = weight / (height * height) * 703;
        return bmi;
    }
}