如何在Java中打印给定变量的倍数？

Question

There are 3 numbers that are given to the user. These three numbers define the multiple, and the range. For example if these three numbers are (3, 6 , 17) the program should print 6,9,12,15. The first number is the base multiple and the second and third numbers are the lowest and the highest numbers (the range). I also know that I do not need all the import statements that I have.

This is what I have so far but I'm not sure how to continue.

import java.util.*;
import java.io.*;
import java.text.*;
import java.lang.Math.*;

public class printMultiplesOf{
    public static void main (String [] args){

        Scanner reader = new Scanner(System.in);
        int num1, num2, num3;

        System.out.println("Enter the 1st number");
        num1 = reader.nextInt();

        System.out.println("Enter the 2nd number");
        num2 = reader.nextInt();

        System.out.println("Enter the 3rd number");
        num3 = reader.nextInt();

        printMultiplesOf(num1, num2, num3);
    }

    public static void printMultiplesOf(int num1, int num2, int num3){
        int start = num2
        int end = num3
        for (int i = num1; i <= num1; i++){
            System.out.println(i + " ");
        }
    }
} 

Answer 1

Loop through all the numbers in the range, and check if it's a multiple.

 public static void printMultiplesOf(int num1, int num2, int num3) {

        for(int i=num2; i<= num3; i++){
            if(i % num1 == 0)
                System.out.print(i +" ");
        }

    }

Answer 2

The main issue here is finding the loop's start and end point. The start point needs to the first number divisible by num1 equal or larger than num2 . You can find it by dividing num2/num1 using floating-point division, ceil the result and multiply it back by num1 . Similarly, the loop's end point should be the largest number divisible by num1 which is less than or equal to num3 . You can find it by dividing num3/num1 using integer division (which would effectively floor the result and then multiplying it back again by num1 . From there on, it's just a matter of looping in steps the size of num1 . Eg:

public static void printMultiplesOf(int num1, int num2, int num3) {
    int start = ((int) Math.ceil((double) num2 / num1)) * num1;
    int end = (num3 / num1) * num1;

    for (int i = start; i <= end; i+= num1) {
        System.out.println (i + " ");
    }
}

Answer 3

This is your function. You simply add your num1 to i each time loop is executed. I tried it and it is working ;)

 public static void printMultiplesOf(int num1, int num2, int num3){
          int multi = num1;
          int start = num2;
          int end = num3;

          for (int i = start; i <= end; i += multi){
               System.out.println(i + " ");
          }
    }