Minigolf 2 (Finished)

You get on stdin one integer per line. The first integer is the target. Find in the rest the number closest to the target and print it to stdout followed by a newline, nothing should go to stderr. No values will be equally close to the target. Each line matches /^[1-9]\d{0,3}\n\z/. Input will be at least two lines.

example input:

here 8 is the target number, 6 is closest (distance two), so the output should be:

Leaderboard

The score for each hole is the total number of characters you need (smaller is better). If your program is more than one line, you must count the newlines inbetween as one character each. The #! line is not counted. If you use options on the #! line, the options themselves are counted, including the leading space and -

   35   darek, ton-, tybalt89
   37   mtve
   38   dave, depesz, oozy
   40   spiff
   41   suo
   44   banshee1, sorroww
   46   lard
   50   TopMach
   53   andys

Some solutions

   ton-      35 -p ($_)=sort{abs$a-$_<=>abs$b-$_}<>
   tybalt89  35 -p ($_)=sort{abs$a-$_<=>abs$b-$_}<>
   darek     35 -p ($_)=sort{abs$a-$_<=>abs$b-$_}<>
   mtve      37 -p $??$\x=abs$?-$\<abs$?-$_:$?||=$_}{
   depesz    38 -p $_=(sort{(abs$a-$_)-abs$b-$_}<>)[0]
   dave      38 -p $_=(sort{(abs$a-$_)-abs$b-$_}<>)[0]
   oozy      38 -p $_=(sort{abs$a-$_<=>abs$b-$_}<>)[0]
   spiff     40 -p $n?$a[abs$n-$_]:$n=$_}{($_)=grep$_,@a
   suo       41 -p for$k(<>){$x[1E5-abs$k-$_]=$k}$_=pop@x
   banshee1  44 $h=<>;print+(sort{abs$a-$h<=>abs$b-$h}<>)[0]
   sorrow    44 $x=<>;print+(sort{abs$a-$x<=>abs$b-$x}<>)[0]
   lard      46 $h=<>;print@{[sort{abs$a-$h<=>abs$b-$h}<>]}[0]
   TopMach   50 $v=<>;$a[($v-$_)**2]=$_ for<>;print"@a"=~/([^ ]+)/	(might break the 2**32 rule)
   andys     53 -l $n=<>;print$n+(sort{abs$a<=>abs$b}map{$_-$n}<>)[0]

After the golf this was found:

   mtve      32 -p ($_)=sort{$a-$b^$a+$b-2*$_}<>

the body is derived from:

    ($a-$_)**2-($b-$_)**2
    $a**2-2*$a*$_-$b**2+2*$b*$_
    $a**2-$b**2-2*$_*($b-$a)
    ($a-$b)*($a+$b)-2*$_*($b-$a)
    ($a-$b)*($a+$b-2*$_)

And only the sign matters (and 0 does not happen), so replace * by ^. This gets you very big positive numbers instead of negative numbers, but perl's internal sort uses them as a signed value, so it maps to negative again.