test example on pre increment and post increment operator

[ragi singh]

hi all
I have a question

Q. Find the output :-
class Compound{
public static void main(String args[])
{
int k=12;
k/=--k;
System.out.println(k);
k*=k++; //Line1
System.out.println(k);

k*=++k; //Line2
System.out.println(k);
}
}
Output is :- 1 1 2



acn anyone explain what happens at line 1 and line 2

[Martin Vanyavchich]

Take a look at this

[Harshit Sethi]

Someone expalin this code's output why not the second SOP gives 2 as output???

[Martin Vanyavchich]

public static void main(String  args[])
{
int k=12;
/* 
'left'k gets divided by ('right'k - 1), since 12/11 is 1.xxx and this is integer division 'left'k gets assigned 1 
(in integer division what's after decimal point gets omitted)
 and 'left'k is now 1, then 'right'k is decremented but that dosen't get saved anywhere (see link above)
*/
k/=--k; 
System.out.println(k);
/*
same magic as above but with multipilication: 'left'k=1*1 == 1
*/
k*=k++; //Line1
System.out.println(k);

/*
'right'k gets incremented befor multiplication and assignment
'left'k=1*2 == 2
*/
k*=++k; //Line2
System.out.println(k);
}
}

Hope it helped

[ragi singh]

Thanks for your post . it helped me especially the article
Post Increment Operator And Assignment

[Harshit Sethi]

But i still have one doubt when the value ++k in k*=++k rewriting it as k=k*(++k); is incremented first then why not the first k on the right hand side of = also gets incremented ???