Right Shift Operator >>

[sai kumar]

Hi all,
A question from a mock exam:
What happens when we attempt to compile and run the follwoing code?
public class Logic{
static int minusOne=-1;
static public void main(String args[]){
int N=minusOne >> 31;
System.out.println("N ="+N);

[sai kumar]

Sorry for the incomplete question, Here it is:
What happens when we attempt to compile and run the follwoing code?

public class Logic
{
    static int minusOne=-1;
    static public void main(String args[])
    {
        int N=minusOne >> 31;
        System.out.println("N ="+N); 
    }
}

Edited by Corey McGlone: Added CODE Tags
[ March 31, 2004: Message edited by: Corey McGlone ]

[Corey McGlone]

So what's your question, Sai? Have you compiled and executed it? What did it produce? Did the output confuse you?
Corey

[fethi makhlouf]

HI Kumar
If you look for the result, it should be cmpilation and runtime without error,
it will also print 1

Look :

public class Logic{
static int minusOne=-1; // binary 1111 1111 1111 1111 1111 1111 1111 1111
static public void main(String args[]){
int N=minusOne >> 31; // it becomes 0000 0000 0000 0000 0000 0000 0000 0001
System.out.println("N ="+N); // it means 1 !

[j zaal]

>> is signed shift operator!!
so -1 >>31 = -1
>>> is unsigned operator
-1 >>> 31 =1

[Vineela Devi]

Hi,
As Zaal has correctly pointed out ,>> is signed rigth shift operator and
-1>>31 results in -1 , but not 1.
when >> is applied on a number, the sign bit of the no is always preserved and the result will have the same sign as tht of the original number.
Vineela.