begin
comment LIBRARY 1;
integer
I;
switch S ≔ S1,
S2,
S3;
I ≔ 1;
goto S[I];
for I ≔ 1,
2,
3 do
begin
S1 :;
OUTREAL(99, 10);
S2 :;
OUTREAL(99, 20);
OUTREAL(99, I)
end;
S3 :;
OUTREAL(99, 30)
end