1)
var
s: string;
begin
s: ='пробел';
writeln(s);
delete(s,4,1);
insert('д',s,4);
writeln(s);
end.
2)
var
i: integer;
a,b: string;
begin
readln(a);
b: ='';
for i: =1 to length(a) do
b: =b+a[i]+' ';
writeln(b);
end.
3)
var
a: string;
begin
readln(a);
if a[2]=a[4] then writeln('равны')
else writeln('не равны');
end.