Show that the following grammar for expressions is ambiguous and provide an alternate unambiguous grammar that...
Show that the following grammar for expressions is ambiguous and provide an alternate unambiguous grammar that defines the same set of expressions.
<expr> ::= <term> | <factor> <term> ::= <factor> | <expr> + <term> <factor> ::= id | <expr> * <factor>
Homework Answers
answer)
If two or more parse trees or left most or right most derivations exist from single string then the grammar is ambiguous.
string is id*id
leftmost derivation 1:
<expr>::=<term>
::=<expr>*<factor>
::=<factor>*<factor>
::=id*<factor>
::=id*id
leftmost derivation 2:
<expr>::=<term>
::=<expr>*<factor>
::=<term>*<factor>
::=<factor>*<factor>
::=id*<factor>
::=id*id
unambiguous grammar is:
<expr>::=<expr>+<term>|<term>
<term>::=<term>*<factor>|<factor>
<factor>::=id
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Show that the following grammar for expressions is ambiguous and
provide an alternate unambiguous grammar that...
1) Using the grammar in Example 3.2, show a completed parse tree for each of the...
1) Using the grammar in Example 3.2, show a completed
parse tree for each of the following statements: a) A = A * (B + (C
* A)) b) A = A * (B + (C))
2) Using the original grammar in Example 3.4, show a
completed parse tree for the statement: A = B + C + A
A Grammar for Simple Assignment Statements PLE 3.2 cassign><id> <expr> cidA BIC «ехpг» — sid + <ехpг» id cexpr> ( <expr>)...
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3. Using the grammar below, show a parse tree and a leftmost derivation for the statement....
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In each case below, show that the grammar is ambiguous, and find an equivalent unambiguous gramnar....
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Consider the following grammar (G1) for simple assignment statements. (The symbols in double quotation marks are...
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Give an unambiguous grammar for the same language generated by the grammar: <fruit>* : -<yellow» | <red>...
Give an unambiguous grammar for the same language generated by
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Question 3: Given the following grammar: assign → id := expr expr → expr + term \ term term -term *factor lfactor factor-(expr) id Using the above grammar, show a leftmost derivation (first five step...
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Given the following ambiguous context free grammar (3x20) 1. (a) Explain why the grammar is ambiguous...
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The questions in this section are based on the grammar given as the following: prog ->...
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1) Using the grammar in Example 3.2, show a completed
parse tree for each of the following statements: a) A = A * (B + (C
* A)) b) A = A * (B + (C))
2) Using the original grammar in Example 3.4, show a
completed parse tree for the statement: A = B + C + A
A Grammar for Simple Assignment Statements PLE 3.2 cassign><id> <expr> cidA BIC «ехpг» — sid + <ехpг» id cexpr> ( <expr>)...
3. Using the grammar below, show a parse tree and a leftmost derivation for the statement. A = ( A + (B)) * C assign <idxpr expr>? <expr> <term> term <term factor factor (<expr>) l <term I <factor l <id> 4. Prove that the following grammar is ambiguous (Give sentence that has two parse trees, and show the parse trees):
Give an unambiguous grammar for the same language generated by
the grammar:
<fruit>* : -<yellow» | <red> <yellow» banana |mango | <empty> <red> ::- cherry | apple | <empty> "Same language" means that the unambiguous grammar can generate exactly the same set of strings as the ambiguous grammar. No more; no fewer. There will of course be a difference in how - by what NTSs and productions - at least some of those strings are generated
* : -
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