N-queen puzzle in 4 lines of Scala

Re:N-queen puzzle in 4 lines of Scala by laumars on Sunday April 10, 2016 @10:19AM (#11466190)

I still feel that's cheating as you're just replacing the semi-colon with braced blocks; effectively it's still being parsed as multiple lines.

I was thinking more along the lines of using the one line conditional:

    condition ? first_expression : second_expression;

    sub nextq {
        (print( "@_\n" ),return) if @_ == (my $size = 8);
        foreach my $col(0..$size-1) {
            my ($row, $next);
            grep ($_ == $col, @_) ? $next=1 : $row=@_;
            grep ($_ == $col-$row--, @_) ? $next=1 : $row=@_;
            grep ($_ == $col+$row--, @_) ? $next=1 : $row=@_;
            nextq(@_,$col) unless $next;
        }
    }   
    nextq();

The `$next` ugliness is due to not being allowed to use the `next` inside a one line conditional. There's probably cleaner ways of doing the above though. But that was only a quick hack.

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Re:N-queen puzzle in 4 lines of Scala by shasta on Sunday April 10, 2016 @10:46AM (#11466313)

It's almost as if "number of lines" isn't particularly meaningful.

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Re:N-queen puzzle in 4 lines of Scala by laumars on Sunday April 10, 2016 @11:15AM (#11466470)

I agree but we've already done that argument to death (eg the Plan 9 vs GNU debates about code "complexity")

This sort of line counting is just for fun.

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Re:N-queen puzzle in 4 lines of Scala by tyingq on Sunday April 10, 2016 @12:18PM (#11466812)

Smaller without being obfuscated:

  sub nextq {
      my $sz=8;
      (print("@_\n"),return) if @_ == $sz;
      o: foreach my $col(0..$sz-1) {
          my($u,$d)=(scalar(@_),scalar(@_));
          for (@_) {next o if($_==$col or $_==$col-$u-- or $_==$col+$d--)}
          nextq(@_,$col);
      }
  }
  nextq();

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Re:N-queen puzzle in 4 lines of Scala by laumars on Sunday April 10, 2016 @02:07PM (#11467401)

Personally I'd consider 1 and 2 character variable names as a form of obfuscation. eg what's the point having a "pseudo-constant" for size if it's named in such a way that isn't immediately obvious that it refers to the size.

Nice code though.

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