Topological Sort

Score: 123.50 (pass)

#!perl -ln
/ /;$`ne$'?$r{$'}{$`}:$x=$r{$`}||={}}while(@n=grep!%{$r{$_}}&&print,keys%r or%r&&exit 1){map delete@$_{@n},\%r,values%r

Score: 131.51 (pass)

#!perl -ln
/ /;$`ne$'?$r{$'}{$`}:$_=$r{$`}||={}}$,=$\;while(@n=grep!%{$r{$_}},keys%r or exit(%r>0)){map delete@$_{@n},\%r,values%r;print@n

Score: 149.46 (pass)

#!perl -ln
/ /;$` ne $'&&$r{$`}{$'}++;$r{$'}||={}}$,=$\;while(%r){my%n;@n{keys%r}++;map delete@n{keys%$_},values%r;%n?print grep delete$r{$_},keys%n:exit 1;

Score: 157.45 (pass)

#!perl -lna
($l,$r)=@F;$l ne $r&&$r{$l}{$r}++;$r{$r}||={}}$,=$\;while(%r){my%n;@n{keys%r}++;map delete@n{keys%$_},values%r;%n?print grep delete$r{$_},keys%n:exit 1;

Score: 162.46 (pass)

#!perl -lna
($l,$r)=@F;$l ne $r&&$r{$l}{$r}++;$r{$r}||={}}$,=$\;while(%r){my%n;@n{keys%r}++;map delete@n{keys %$_},values %r;%n||exit 1;print grep delete$r{$_},keys(%n);