Removing ambiguity-from-cfg
- 2. Group Members: 1. Muradul Islam Jamil (152-35-1203) 2. Mahadi Hasan Joy (152-35-1207) 3. Mazed Mourshed (152-35-1215) Md. Anwar Hossen Lecturer, Dept. of Software Engineering Daffodil International University 2
- 3. AMBIGUITY IN CFG If a context free grammar has more than one derivation tree for some string, it is called an ambiguous grammar. There exist multiple right-most or left-most derivations for some string generated from that grammar. 3
- 4. PROBLEM Check whether the grammar G with production rules − S → AB | aaB A → a | Aa B → b 4
- 5. SOLUTION Let’s find out the derivation tree for the string “aab". It has two leftmost deriv i) S → aaB → aab ii) S → AB →AaB → aaB → aab 5
- 6. ANOTHER PROBLEM Check whether the grammar G with production rules − S → S + S | S * S | a 6
- 7. SOLUTION Let’s find out the derivation tree for the string “a+a+a". It has two leftmost d i) S → S + S → S + S + S → a + a + S → a + a + a ii) S → S + S → S + S + S → S + a + a → a + a + a 7
- 8. SOLUTION Let’s find out the derivation tree for the string “a+a*a". It has two leftmost de i) S → S + S → a + S → a + S * S → a + a * a ii) S → S * S → S + S * S → a + a * S → a + a * a 8
- 9. THANK YOU 9