Java Puzzle operator confusion

Why does this 
int _=1, __=2;
int j = __ ^_^ __, k = __-- -+- _ -+- --__;
System.out.println(j + " " + k);
print the following? 
1 3

Comments

  1. Przemysław Bielicki7 December 2011 at 13:04

    This comment has been removed by the author.

    ReplyDelete
  2. Przemysław Bielicki7 December 2011 at 13:14

    right expressions in Java are evaluated from left to right (my mistake) so let's think like Java now:

    i = 2
    j = 1
    i-- + j = 3
    i-- + j + --i = 3 (i is already evaluated and equals 1 so --i = 0)

    right?

    ReplyDelete
  3. Peter Lawrey7 December 2011 at 13:21

    Brillant, you made it look easy. :)

    ReplyDelete
  4. vasste7 December 2011 at 14:38

    10
    ^01
    ^10
    =
    01
    2 + 1 + 0 = 3

    ReplyDelete
  5. Przemysław Bielicki7 December 2011 at 15:12

    to compare:
    Java 1 3
    C/C++ 1 4
    Python 1 5
    Perl 1 3

    ReplyDelete
  6. Peter Lawrey7 December 2011 at 15:28

    @Przemyslaw, Thank you for the comparison. ;)

    ReplyDelete

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