What makes that difference By putting extra zero on left hand side

Question

Just started to learn programming could u explain whats difference between them

public class tst {

    public static void main(String args[]){
        int mk=1200;
        System.out.println(mk);
    }

}

public class tst {

    public static void main(String args[]){
        int mk=01200;
        System.out.println(mk);
    }
}

First one gave result 1200 while second one 640.

score 4 · Answer 1 · answered Apr 05 '16 at 06:57

4

A leading 0 makes the compiler parse the number as an octal number (radix 8). The decimal value of 01200 octal is 640.

answered Apr 05 '16 at 06:57

Eran

387,369
54
702
768

is that because System.out.println??As according to me it converts the value into String?? – mayank kumar Apr 05 '16 at 08:50
@mayankkumar println converts an integer to a String of its decimal representation. – Eran Apr 05 '16 at 08:52

score 2 · Answer 2 · answered Apr 05 '16 at 06:58

A leading zero implies an octal literal; so 01200 is base 8 which, in decimal, is 640.

Essentially this is paying homage to older times where octal literals were much more common. These days though it's more likely to be a distraction and cause for confusion. There are movements to propose the more deliberate 0o notation for an octal literal.

What makes that difference By putting extra zero on left hand side

2 Answers2