Loops question

[Rob M Jones]

Hi everyone, I am currently studying java and came across this question on one of the practice exams. I have stepped through each iteration of the loops but am stumped as to why x is never increased to 4 when i is set to 1. Can anyone shed some light on this?
Thanks!

int x = 3;
 for(int i = 0; i < 3; i ++) {
 if(i == 1) x = x ++;
 if (i % 2 == 0 && x % 2 == 0) System.out.print(" . ") ;
 if (i % 2 == 0 && x % 2 == 1) System.out.print (" - ") ;
 if (i == 2 ^ x == 4) System.out.print (",") ;
 }
System.out.println ("<") ;

By the way the output is --,<

[amro talaat]

Rob M Jones wrote:Hi everyone, I am currently studying java and came across this question on one of the practice exams. I have stepped through each iteration of the loops but am stumped as to why x is never increased to 4 when i is set to 1. Can anyone shed some light on this?
Thanks!

int x = 3;
 for(int i = 0; i < 3; i ++) {
 if(i == 1) x = x ++;
 if (i % 2 == 0 && x % 2 == 0) System.out.print(" . ") ;
 if (i % 2 == 0 && x % 2 == 1) System.out.print (" - ") ;
 if (i == 2 ^ x == 4) System.out.print (",") ;
 }
System.out.println ("<") ;

By the way the output is --,<

try if else ???

[Carey Brown]

Rob M Jones wrote:Hi everyone, I am currently studying java and came across this question on one of the practice exams. I have stepped through each iteration of the loops but am stumped as to why x is never increased to 4 when i is set to 1. Can anyone shed some light on this?
Thanks!

int x = 3;
 for(int i = 0; i < 3; i ++) {
 if(i == 1) x = x ++;
 if (i % 2 == 0 && x % 2 == 0) System.out.print(" . ") ;
 if (i % 2 == 0 && x % 2 == 1) System.out.print (" - ") ;
 if (i == 2 ^ x == 4) System.out.print (",") ;
 }
System.out.println ("<") ;

By the way the output is --,<

Try

if(i==1) x++;

[Christophe Verré]

Check this FAQ.

[Ankit Dan]

why x is never increased to 4 when i is set to 1.

you can see that you have assigned the value of post increment x to x i.e x=x++
so x is assigned a value before it is incremented
you can try x = ++x
or simply x++ or ++x

hope it helps


Ankit

[Campbell Ritchie]

The idea of that question may be to find out whether you can see
i = i++;
and realise there is a trap for the unwary!