casio fx-3650p計算機programme問題，急

ClrMemory: ?→A: ?→B: ?→C: B2 - 4AC→C:
(√( C ) - B)┘(2A→X◢ (- √( C ) - B)┘(2A→Y◢
Lbl 0: 1→B: X→C: Lbl 1: B→D: Fix 0:
X - B Rnd( XB→B: B=0 => 1→D: Ans => Goto 2:
D→X: Rnd( Abs ( B-1→D: DC - Rnd( DC => Goto 1:
Lbl 2: Norm 1: D◢ - DC◢ AD→A: Y→X: M=0→M:
Ans => Goto 0: A

本人計算機是casio fx-3650p，請問第5行"Abs"點打?