Section 9 - Regular languages Flashcards
1
Q
what does * mean in regular expressions
A
indicates there are zero or more of the preceeding element
2
Q
what does + mean in regular expressions
A
indicates that there is one or more of the preeceding element
3
Q
what does ? mean in regular expressions
A
indicates there are zero or one of the preceding element
4
Q
what is a Turing machine
A
- a theoretical machine that can simulate any computer algorithm
- consists of an infinetly long strip of tape divided into quares and a read/write head
5
Q
what is a universal turing machine
A
a theoretical machine that can carry out any computable sequence
6
Q
what is a meta language
A
the rules of programming languages must be defined, in order for them to be translated into machine code
7
Q
what is backus-naur form (bnf)
A
a meta language that can define contructs more succenctly than regular expressions
8
Q
::=
A
‘is defined by’
9
Q
<’…’>
A
a variable
