Ambiguity( Cont) aA grammar is ambiguous D if it has more than one parse tree for any string ■ Ambiguity is bad lEaves meaning of some programs ill-defined Ambiguity is common in programming languages D Arithmetic expressions 口|F-THEN-ELSE6 Ambiguity (Cont.) ◼ A grammar is ambiguous if it has more than one parse tree for any string ◼ Ambiguity is bad Leaves meaning of some programs ill-defined ◼ Ambiguity is common in programming languages Arithmetic expressions IF-THEN-ELSE