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A context free language is called ambiguous if _________

A context free language is called ambiguous if _________ Correct Answer It has 2 or more right derivations for some terminal string ѡ є L (G)

A context-free grammar (CFG) is a set of recursive rewriting rules (or productions) used to generate patterns of strings.

Related Questions

Let L1, L2 be any two context-free languages and R be any regular language. Then which of the following is/are CORRECT? I. L1 ∪ L2 is context-free II. L̅1 is context-free III. L1 – R is context-free IV. L1 ∩ L2 is context-free
Let L(R) be the language represented by regular expression R. Let L(G) be the language generated by a context free grammar G. Let L(M) be the language accepted by a Turing machine M. Which of the following decision problems are undecidable? I. Given a regular expression R and a string w, is w ∈ L(R)? II. Given a context-free grammar G, is L(G) = ϕ? III. Given a context-free grammar G, is L(G) = ∑* for some alphabet ∑? IV. Given a Turing machine M and a string w, is w ∈ L(M)?  
Consider the following languages L1 = {ap | p is a prime number} L2 = {anbmc2m | n ≥ 0, m ≥ 0} L3 = {anbnc2n | n ≥ 0} L4 = {anbn | n ≥ 1} Which of the following are CORRECT? I. L1 is context-free but not regular. II. L2 is not context-free III. L3 is not context-free but recursive. IV. L4 is deterministic context-free
Read the passage carefully and choose thebest answer to each question out of the four alternativesand click the button corresponding to it. To know language is to be able to speak it; even a childwho does not yet attend school can speak his or herlanguage. In order to speak a language it is important tolisten to it and to read a few pages in it everyday. A childpicks up language and learns to talk just as (s)he learnsto walk. Walking and talking comes naturally to a child asit grows. In our country, a child may grow up speakingmore than one language, if these languages are spoken inthe home and in the neighbourhood. we call this multilingualism. A child speaks a language or languagesmuch before (s)he starts going to school. To know alanguage then is first of all to be able to speak it as easilyand naturally as a tree year old child does. Later on thechild will learn to read and write in that language. In orderto read and write in a language, one has to speak it. But itis possible to speak a language but not able to read orwrite in it. A baby does not speak until it is nine monthsold but it understands a few words at six months of age.It has been listening ever since it was born, and even alittle before that. So the first strategy in speaking alanguage is to listen. It is necessary for one to __________ the language before(s)he writes in that language.
Consider the language L = {an |n ≥ 0} ∪ {anbn| n ≥ 0} and the following statements. I. L is deterministic context-free. II. L is context-free but not deterministic context-free. III. L is not LL(k) for any k. Which of the above statements is/are TRUE?
Read the passage carefully and choose thebest answer to each question out of the four alternativesand click the button corresponding to it. To know language is to be able to speak it; even a childwho does not yet attend school can speak his or herlanguage. In order to speak a language it is important tolisten to it and to read a few pages in it everyday. A childpicks up language and learns to talk just as (s)he learnsto walk. Walking and talking comes naturally to a child asit grows. In our country, a child may grow up speakingmore than one language, if these languages are spoken inthe home and in the neighbourhood. we call thismultilingualism. A child speaks a language or languagesmuch before (s)he starts going to school. To know alanguage then is first of all to be able to speak it as easilyand naturally as a tree year old child does. Later on thechild will learn to read and write in that language. In orderto read and write in a language, one has to speak it. But itis possible to speak a language but not able to read orwrite in it. A baby does not speak until it is nine monthsold but it understands a few words at six months of age.It has been listening ever since it was born, and even alittle before that. So the first strategy in speaking alanguage is to listen. To know a language one must be able to?
Which of the following statements is/are TRUE? (a) The grammar S → SS | a is ambiguous. (Where S is the start symbol) (b) The grammar S → 0S1 | 01S |e is ambiguous. (The special symbol e represents the empty string) (Where S is the start symbol) (c) The grammar (Where S is the start symbol) S → T / U T → x S y | xy | ϵ U → yT generates a language consisting of the string yxxyy.
Which of the following problems are decidable? 1) Does a given program ever produce an output? 2) If L is a context-free language, then, is L̅  also context-free? 3) If L is a regular language, then, is L̅  also regular? 4) If L is a recursive language, then, is L̅  also recursive? 
Consider four processes P, Q, R, and S scheduled on a CPU as per round-robin algorithm with a time quantum of 4 units. The processes arrive in the order P, Q, R, S, all at time t = 0. There is exactly one context switch from S to Q, exactly one context switch from R to Q, and exactly two context switches from Q to R. There is no context switch from S to P. Switching to a ready process after the termination of another process is also considered a context switch. Which one of the following is NOT possible as CPU burst time (in time units) of these processes?  
Which of the following are determinants in transactional communication? A. Social context B. Cultural context C. Relational context D. Legal context E. Delayed context Choose the correct answer from the options given below: