Var
S: string;
Const
St1: string = 'hello world mother ****er';
St2: string = 'my world is good hello';
Begin
Writeln('First string: ',st1);
Writeln('Second string: ',st2);
Writeln('Double words:');
st1:=st1+' ';
while st1<>'' do
Begin
IF pos(copy(st1,1,pos(' ',st1)-1),st2)<>0 then
writeln(copy(st1,1,pos(' ',st1)-1));
delete(st1,1,pos(' ',st1));
End;
End.