[amture106]

Hey guys,

I'm writing a program that does a lot of things, but one of them is to check if the user input a 3 digit number then do stuff, but if a user input 2 or 4+ digit numbers then the program don't do any thing.

I wrote this chunk of code

do{
			System.out.println("Enter a 3-digit number: ");
			int input = scan.nextInt();
		}while (input >= 100 || input < 1000);

but it doesn't check if the input is 3 digits.

So some help please.

This post has been edited by amture106: 09 October 2012 - 07:07 PM

[Kinaces]

Well first this will not even compile. How can you check a condition on a variable that will only be created if the condition is true. You need to make input outside of the do/while loop. You do not have to instantiate it outside of the loop, just make the variable outside the loop. Second of all, you're testing if input IS a 3 digit number, and as long as it is keep getting input.

[amture106]

sorry my bad I meant

int input;
do{
			System.out.println("Enter a 3-digit number: ");
		 input = scan.nextInt();
		}while (input >= 100 || input < 1000);

now it will compile and still won't work

[Zoquo]

If you are trying to check to see if it is a three-digit number, the condition would be AND not OR.

But if you are checking to see if it is NOT, then just change the OR to an AND and throw a NOT before it.

This post has been edited by Zoquo: 09 October 2012 - 08:13 PM

[burakaltr]

import java.util.Scanner;

public class Digit {
	public static void main(String...h){
	int input=333;
	Scanner scan=new Scanner(System.in);
	boolean b=true;
	while ( b ){
		
	System.out.println("Enter a 3-digit number: ");
	input = scan.nextInt();
		b =!(input >= 100 && input < 1000);
	}
//execution block goes here !
									}
}

This post has been edited by burakaltr: 09 October 2012 - 08:23 PM

[CasiOo]

I like that both of you suggested putting a not around it

Why not just

do {
    //Ask for input
}
while (input < 100 || input > 1000);