($a,$b,$c,$d)=glob<>;
$x=2;$y=0;$p=1;

sub a{$o.="@_\n";++$y}
sub f{$p=pop;a($p,$x),$p=$x++for 2..pop}

if($a==$c){
	!--$a?$d=0:a 0,1 if $b==$c;
	f$b-$c,1;
	a$p,0;
	f$a,0;
}else{
	f$b,1;
	f$a-$c,0;
	a$p,$b-$c+1 if $c;
}

print$d<$y?-1:"$x $y\n$o"