//Решение №1:
//PascalABC.NET
begin
readstring().Replace('1', '').Println;
end.
//Решение №2:
var
N, newN, tmp, count: integer;
begin
read(N);
tmp := N;
count := 1;
while (tmp > 0) do
begin
if (tmp mod 10 <> 1) then
begin
newN := newN + (tmp mod 10) * count;
count := count * 10;
end;
tmp := tmp div 10;
end;
write(newN);
end.