Follow
cheat: terminal or symbol after the variable
Algorithm
- If S is the start symbol, ex: S -> Ab | c, then $ is the Follow value of S
- If A -> αBβ, then all First of β is the Follow of B except ε
- a. A -> αB, then all Follow of A is the Follow of B
- b. A -> αBβ and First of β is ε, then all Follow of A is the Follow of B
Special case
If A -> α, i.e production result contains only 1 variable, add ε in front of the variable to conform to rule 3.a. A -> α*B
You can only find the follow values of the variable on the lines before it
The number of follow values is equivalent to the number of producer variables in our grammar
Cheat
Ex:
Abc = b
A + b = +
Status: #idea
Tags: compilation-techniques > Final ExamCompilation Techniques NotesMid Exam
RE to DFA
RE to E-NFA to DFA
Context Free Grammar
Top down parsing
Final Exam
Bottom Up Parsing
Directed Acyclic Graph
TAC, Triples, Quadriples
Intermediate Code Generator
Code Generator
Annotated Parse Tree
Three Address Statement
resources:
https://www.youtube.com/watch?v=6yRB6dszSUo&ab_channel=HIMTIBINUS
* [x] watch all alvina aulia vids
* [x] watch responsi
(after OS)
* [ ] try example questions from kenny
* [ ] try example questions from others
* [ ] practice weak, compilation-techniques > Mid ExamCompilation Techniques NotesMid Exam
RE to DFA
RE to E-NFA to DFA
Context Free Grammar
Top down parsing
Final Exam
Bottom Up Parsing
Directed Acyclic Graph
TAC, Triples, Quadriples
Intermediate Code Generator
Code Generator
Annotated Parse Tree
Three Address Statement
resources:
https://www.youtube.com/watch?v=6yRB6dszSUo&ab_channel=HIMTIBINUS
* [x] watch all alvina aulia vids
* [x] watch responsi
(after OS)
* [ ] try example questions from kenny
* [ ] try example questions from others
* [ ] practice weak, Bottom Up ParsingBottom Up Parsingsteps
1. Perform Go To operation
1. Find Follow value
1. Create SLR Table
1. Search through parsing
no need to remove Left Recursive
Example Alvina Aulia Bottom Up Parsing
1. E -> E + T | T
1. T -> T * F | F
1. F -> (E) | id
Perform Go To operation:
i0:
E' -> .E
1. E -> .E + T
1. E -> .T
1. T -> .T * F
1. T -> .F
1. F -> .(E)
1. F -> .id
(Input E to i0)
i1:
E' -> E.
1. E -> E. + T
(Input T to i0)
i2:
2. E -> T.
3. T -> T. * F
(Input F to i0)
i3:
4. T -> F.
Screenshot 2024-11-17, Top down parsingTop down parsingsteps
1. no left recursive and left factoring
1. find First values (as many grammars that we have)
1. find Follow value (as many grammars that we have)
1. make Parsing Table
1. search through the parsing
Example Alvina Aulia Top Down Parsing
1. E -> TE'
1. E' -> +TE' | ε
1. T -> FT'
1. T' -> \FT'* | ε
1. F -> (E) | id
First Values:
1. First E = (, id (this is from E -> T -> F)
1. First E' = +, ε
1. First T = (, id
1. First T' = \*, ε
1. First F = (, id
Follow Values:
1. Follow E = $, )