Need help with simple program.

[Justin Meyer]

Ok so i need help with a simple program that i have almost gotten all of it correct. So basically i need to have a phone number generated randomly every time it is run and the first 3 digits cannot have a 8 or 9 and the second set of 3 digits cannot be higher than 743. I have gotten almost all of it except for the fact that i cannot seem to figure out why when a number is lower than 3 digits for the first 3 numbers it doesnt add a 0 in front of it. For example it will print a number like 705 for the last 4 digits when i need it to print 0705. Anyways heres my code if anybody can help me out, should be pretty easy its a high school level program.

 

import java.util.Random;

public class phoneNumber

{

  public static void main (String[] args)

  {

    Random generator = new Random();

    int num123, num456, num7890;

    num123 = generator.nextInt(777) + 1;

    if (num123 <= 99) num123 = (+ 0 + num123);

    

    num456 = generator.nextInt(743) + 1;

    if (num456 <= 99) num456 = (+ 0 + num456);

      

    num7890 = generator.nextInt(9999) + 1;

    if (num7890 <= 999) num7890 = (+ 0 + num7890);

    

    System.out.println("Your new random phone number is " + num123 + "-" + num456 + "-" + num7890);

  }

}

 

P.S. Sorry if my code is inefficient or isnt very good im pretty new to coding.

Edited September 15, 2015 by Justin Meyer

[Guest]

use code thingy madohicker  

[jimakos234]

num7890 = (+ 0 + num7890);

You are doing something like 1+0 and you expect to get 01

You will get 1+0=1

[Justin Meyer]

num7890 = (+ 0 + num7890);

You are doing something like 1+0 and you expect to get 01

You will get 1+0=1

So how do i fix it?

[jimakos234]

So how do i fix it?

The simple and cheap way would be to use some if conditions before printing checking if the number is lower than 3 digits.

Otherwise give me a sec, i have not a java ide installed since i reinstalled windows

[amp88]

I have gotten almost all of it except for the fact that i cannot seem to figure out why when a number is lower than 3 digits for the first 3 numbers it doesnt add a 0 in front of it. For example it will print a number like 705 for the last 4 digits when i need it to print 0705.

One general approach for this (which you should be able to reuse lots of times when outputting information) is to use a NumberFormat. The NumberFormat can be customised for your use (in this case, the minimum of 4 digits, which will prepend a '0' on numbers of less than 1000) and it doesn't alter the underlying data - only the presentation of said data. Here's an example for your case:

NumberFormat integerFormat = NumberFormat.getIntegerInstance();integerFormat.setMinimumIntegerDigits(4);integerFormat.setGroupingUsed(false);int[] numbersToPrint = {1, 10, 100, 1000};for(int numberToPrint : numbersToPrint) {	System.out.println("numberToPrint: "+integerFormat.format(numberToPrint));}

Output:

numberToPrint: 0001numberToPrint: 0010numberToPrint: 0100numberToPrint: 1000

[jimakos234]

Damn i had to mess around with java 2-3 years...

        NumberFormat integerFormat = NumberFormat.getIntegerInstance();        NumberFormat integerFormat2 = NumberFormat.getIntegerInstance();        integerFormat.setMinimumIntegerDigits(3);        integerFormat.setGroupingUsed(false);        integerFormat2.setMinimumIntegerDigits(4);        integerFormat2.setGroupingUsed(false);        Random generator = new Random();        int num123, num456, num7890;        do{ //if it cant contain 8 or 9 u had it set at 777, which is wrong, because 689 would be a correct input from the programm            num123 = generator.nextInt(999) + 1;                    }while(String.valueOf(num123).contains("8")||String.valueOf(num123).contains("9"));        num456 = generator.nextInt(743) + 1;        num7890 = generator.nextInt(9999) + 1;        System.out.println("Your new random phone number is " + integerFormat.format(num123)                 + "-" + integerFormat.format(num456) + "-" + integerFormat2.format(num7890)); 

[Justin Meyer]

Awesome, thanks everyone i fixed it and now i just gotta turn it in. I appreciate the help...

[Satlen]

Awesome, thanks everyone i fixed it and now i just gotta turn it in. I appreciate the help...

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