import java.util.Arrays;
import java.util.Scanner;

public class AnArrayCalculator {

	public static void main(String[] args) {
		int choice = getMenuOption();
		Scanner scan = new Scanner(System.in);
		switch (choice) {
		case 1:
			System.out.println("How many values are in the array?");
			int size1 = scan.nextInt();
			double[] operand1 = getOperand("Enter the values in the first array, separated by spaces:", size1);
			double[] operand2 = getOperand("Enter the values in the second array, separated by spaces:", size1);
			System.out.println("The result is: " + Arrays.toString(add(operand1, operand2)));
		case 2:
			System.out.println("How many values are in the array?");
			int size2 = scan.nextInt();
			double[] operand3 = getOperand("Enter the values in the first array, separated by spaces:", size2);
			double[] operand4 = getOperand("Enter the values in the second array, separated by spaces:", size2);
			System.out.println("The result is: " + Arrays.toString(subtract(operand3, operand4)));
		case 3:
			System.out.println("How many values are in the array?");
			int size3 = scan.nextInt();
			double[] operand5 = getOperand("Enter the values in the first array, separated by spaces:", size3);
			double[] operand6 = getOperand("Enter the values in the second array, separated by spaces:", size3);
			System.out.println("The result is: " + Arrays.toString(multiply(operand5, operand6)));
		default:
			System.exit(0);
		}

	}

	public static int getMenuOption() {
		System.out.println(
				"Menu \n1. Add \n2. Subtract \n3. Miltiply \n4. Divide \n5. Dot Product \n6. Generate Random Array \n7. Quit");
		System.out.println("What would you like to do?");
		Scanner scan = new Scanner(System.in);
		int number = scan.nextInt();
		return number;
	}

	public static double[] getOperand(String prompt, int size) {
		System.out.println(prompt);
		Scanner scan = new Scanner(System.in);
		String values = scan.nextLine();
		Scanner input = new Scanner(values);
		double[] operand = new double[size];

		while (input.hasNextDouble()) {
			for (int i = 0; i < size; i++) {
				operand[i] = input.nextDouble();
			}
		}
		return operand;
	}
	public static double[] add(double[] operand1, double[] operand2) {
		double[] sum = new double[operand1.length];
		for (int i = 0; i < operand1.length; i++) {
			sum[i] = operand1[i] + operand2[i];
		}
		return sum;
	}
	public static double[] subtract(double[] operand1, double[] operand2) {
		double[] difference = new double[operand1.length];
		for (int i = 0; i < operand1.length; i++) {
			difference[i] = operand1[i] - operand2[i];
		}
		return difference;
	}
	public static double[] multiply(double[] operand1, double[] operand2) {
		double[] product = new double[operand1.length];
		for (int i = 0; i < operand1.length; i++) {
			product[i] = operand1[i] * operand2[i];
		}
		return product;
	}
}