program PascalGuru;
var
p: integer; { описание переменных }
i, j, n: integer;
s, x, sogl: string;
A: array [1 .. 100] of string;
vxod: boolean;
begin
write('Vvedite stroky (cerez probel): ');
readln(s);
j := 0;
repeat
inc(j);
p := pos(' ', s);
x := copy(s, 1, p - 1);
A[j] := x;
delete(s, 1, p);
until p = 0;
n := j;
delete(s, length(s), 1);
A[n] := s;
{ ---------------- }
sogl := 'бвгдйжзклмнпрстфхцчшщ';
writeln;
for i := 1 to length(sogl) do
begin
vxod := true;
for j := 1 to n do
if odd(j) then
if pos(sogl[i], A[j]) = 0 then
vxod := false;
if vxod then
write(sogl[i]);
end;
readln;
end.