精華區beta NTU-Exam 關於我們 聯絡資訊
課程名稱︰自動機與形式語言 課程性質︰系必修 課程教師︰項潔 開課學院:電資學院 開課系所︰資工系 考試日期(年月日)︰2012/11/06 考試時限(分鐘):120min 是否需發放獎勵金:是 (如未明確表示,則不予發放) 試題 : Problem 1.(10points) Let A be the set of all infinite sequences over {0,1}. Show that A is uncountable. Problem 2.(15points) Prove that L={0^m1^n: m,n≧0 are integers with m≠n} is not regular. Problem 3.(20points) A grammar G = (V,Σ,R,S) is regular if all rules in R are of the form: A→aB,A→a,or A→ε,when A,B 屬於 V and a 屬於Σ Show that a language L is regular if and only if there is a regular grammar G such that L(G)=L. Problem 4.(20points) Is the class of context-free language closed under ∪,。,*,∩,-(complement)? Justify your answer:[Hint:Do in that order.] Problem 5.(20points) Answer following question: (a)Let C be a context-free language and R be a regular language. Prove that the language C∩R is context-free. (b)Use part(a) to show that the language A={w|w屬於{a,b,c}* and contains equal numbers of a,b and c} is not context-free. Problem 6.(15points) Let D ={xy|x,y 屬於 {0,1}* and |x|=|y| but x≠y}. Show that D is context-free. -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.112.30.139 ※ 編輯: a123zyx 來自: 140.112.30.139 (11/06 14:59) ※ 編輯: a123zyx 來自: 140.112.30.139 (11/06 14:59)