Java 实例 相乘两个数字

import java.util.Scanner;

public class Demo {

    public static void main(String[] args) {

        /* This reads the input provided by user
         * using keyboard
         */
        Scanner scan = new Scanner(System.in);
        System.out.print("Enter first number: ");

        // This method reads the number provided using keyboard
        int num1 = scan.nextInt();

        System.out.print("Enter second number: ");
        int num2 = scan.nextInt();

        // Closing Scanner after the use
        scan.close();

        // Calculating product of two numbers
        int product = num1*num2;

        // Displaying the multiplication result
        System.out.println("输出： "+product);
    }
}

Enter first number: 15
Enter second number: 6
输出： 90

import java.util.Scanner;

public class Demo {

    public static void main(String[] args) {

        /* This reads the input provided by user
         * using keyboard
         */
        Scanner scan = new Scanner(System.in);
        System.out.print("Enter first number: ");

        // This method reads the number provided using keyboard
        double num1 = scan.nextDouble();

        System.out.print("Enter second number: ");
        double num2 = scan.nextDouble();

        // Closing Scanner after the use
        scan.close();

        // Calculating product of two numbers
        double product = num1*num2;

        // Displaying the multiplication result
        System.out.println("输出： "+product);
    }
}

Enter first number: 1.5
Enter second number: 2.5
输出： 3.75