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