begin comment 'LIBRARY' 1; real X, Y, Z, U; integer I, CASE; procedure COMPARE(U, V); value U, V; real U, V; begin CASE ≔ CASE + 1; if U ≠ V then begin OUTREAL(99, U); OUTREAL(99, V); OUTREAL(99, CASE) end; end; CASE ≔ 0; X ≔ 1·2; Y ≔ 16·96; Z ≔ - 13·4; for I ≔ 1 step 1 until 10 do begin COMPARE( - X × Y, - (X × Y)); COMPARE( - X / Y, - (X / Y)); COMPARE(X + Y + Z, (X + Y) + Z); COMPARE(X × Y × Z, (X × Y) × Z); COMPARE(X / Y / Z, (X / Y) / Z); COMPARE(X × Y / Z, (X × Y) / Z); COMPARE(X⭡2 / Y, (X × X) / Y); COMPARE(X × Y⭡2, X × (Y × Y)); U ≔ 1·01 × X; X ≔ 1·01 × Y; Y ≔ 1·01 × Z; Z ≔ U; end; OUTREAL(99, 0) end