/* 
 * Program to search the maximum value from the standard input by using ArrayList. 
 */
package algorithms;

import javax.swing.*;
import java.util.ArrayList;
import java.util.Scanner;

public class MaxValue {
    public static void main(String[]args) {
        // Read the integers and store them in the list
        ArrayList<Integer> numbers = readNumbersFromStandInput();
        // Echo check
        System.out.println(numbers);
        // Find the maximum value
        Integer max = maxValue(numbers);
        // And, print it out
        System.out.println(max);
    }

    private static Integer maxValue(ArrayList<Integer> numbers) {
        // Initial champion
        Integer champion = numbers.get(0);
        // Look at each element as a challenger and if the challenger is greater than the champion,
        // replace the champion with the challenger
        for ( Integer challenger : numbers){
            if ( challenger > champion ) {
                champion = challenger;
            }
        }
        // Return the champion
        return champion;
    }

    private static ArrayList<Integer> readNumbersFromStandInput() {
        // Establish a place to store the numbers
        ArrayList<Integer> numbers = new ArrayList<>();
        // Prepare to read the numbers
        Scanner scanner = new Scanner(System.in);
        System.out.println("Enter some positive integers, " + "followed by a negative integers");
        // Read and store the numbers in the ArrayList
        Integer readNumber = scanner.nextInt();
        while (readNumber >= 0) {
            numbers.add(readNumber);
            readNumber = scanner.nextInt();
        }
        // Return the numbers
        return numbers;
    }
}