Calculating FIRST

1. FIRST(a)={a} for all terminals a.
2. Initialize FIRST(A)=φ for all nonterminals A
3. If A → ε is a production, add ε to FIRST(A).
4. For each production A → Y₁ ... Y_n,
   1. add to FIRST(A) any terminal a satisfying
      1. a is in FIRST(Y_i) and
      2. ε is in all previous FIRST(Y_j).
   2. add ε to FIRST(A) if ε is in all FIRST(Y_j).
   Repeat step 4 until nothing is added.
5. FIRST of any string X=X₁X₂...X_n is initialized to φ and then
   1. add to FIRST(X) any non-ε symbol in FIRST(X_i) if ε is in all previous FIRST(X_j).
   2. add ε to FIRST(X) if ε is in every FIRST(X_j). In particular if X is ε, FIRST(X)={ε}.

Calculating Follow

1. Initialize FOLLOW(S)=$ and FOLLOW(A)=φ for all other non-terminals A.
2. For every production A → α B β, add all of FIRST(β) except ε to FOLLOW(B).
3. Apply the following rule until nothing is added to any FOLLOW set.
   For every production ending in B, i.e. for
       A → α B and for
       A → α B β, where FIRST(β) contains ε,
   add all of FOLLOW(A) to FOLLOW(B).

PREDICTIVE PARSING TABLE

For each production A → α

1. For each terminal a in FIRST(α), add A → α to M[A,a].
2. If ε is in FIRST(α), then add A → α to M[A,b] (resp. M[A,$]) for each terminal b in FOLLOW(A) (if $ is in FOLLOW(A)).

SLR ACTION TABLE

1. If A→α·bβ is in I_i for b a terminal, then ACTION[i,b]=shift j, where GOTO(I_i,b)=I_j.
2. If A→α· is in I_i, for A≠S', then, for all b in FOLLOW(A), ACTION[i,b]=reduce A→α.
3. If S'→S· is in I_i, then ACTION[i,$]=accept.