open(A,"1.txt");while(my $line =){ $save1{$line} = 1;}close(A);open(B,"2.txt");while(my $line =){ if(! exists $save1{$line}){print $line;} else{$save2{$line} = 1;}}close(B);while(($key,$value)=each %save1){ if(!exists $save2{$key}){print $key;}}
