CS547T SPRING 2007

ASSIGNMENT 5/ QUIZ 5


     April 2007
Su Mo Tu We Th Fr Sa 
      17 18 19 20 21
            TODAY
22 23 24 25 26 27 28
29 30
   LAST CLASS


JUST CHECKING YOUR ATTENTION:

True or False

1.  All recursively enumerable languages are also recursive languages.

2.  There exists a universal Turing machine that can simulate a decider of a
	language L, so it too can decide L.

3.  A NPDA can be encoded just like a TM can be encoded, where each
	choice of transition can simply be listed, and a NTM can simulate
	this NPDA just like the UTM simulates a DTM, using its nondeterminism
	to reflect the NPDA's nondeterminism.

4.  All Turing machines halt on finite input.

5.  If L is a finite language, then there is a TM that decides L.

6.  If M is a TM s.t. its language L(M) is finite, then M must halt on all inputs.

7.  If there is a Turing machine deciding each of the languages L_1, L_2, and L_3,
	and these languages have no intersection, and L_1 union L_2 union L_3 is
	Sigma.gif^^*^^^, then L_1 is recursive.

8.  If M, a DTM accepts L, then there is an M', an NTM that decides L.

9.  A 2-tape DTM can simulate a 1-tape machine where there is no limit on
	the left side (just as there is no limit on the right side) of the
	tape.

10.  The strings over {0,1}^^*^^^ that properly encode Turing machines can be enumerated 
	in order of length.