, , LL(1)- .
A → Aa ( A)
A → a
a - A. , , LL(1)-,
A → BC
B → CD
C → AE
, , , , , , ( , LL(1)-).
S → Aa
A → Bb
B → Cc
C → Dd
C → e
D → Az
, A, B, C, D. , : S, A, B, C, D.
Xi → Xj γ,
Xi Xj , γ . , j ≥ i, . , . :
D → Az
A D . A, , A .
D → Bbz
B D , , :
D → Ccbz
:
D → ecbz
D → Ddcbz
:
S → Aa
A → Bb
B → Cc
C → Dd
C → e
D → Ddcbz
D → ecbz
, . , Z
D → ecbz
D → Ddcbz
D → ecbz
D → ecbzZ
Z → dcbz
Z → dcbzZ
, D
(ecbz) (dcbz)*
, , A r + s , r , s , ..
A → Aα 1, A → Aα 2,..., A → Aα r
A → β 1, A → β 2,..., A → β s
:
, A (β 1 | β 2 |... | β s) (α 1 | α 2 |... | α r) *
|
|
, ( ), LL(1)-, .. , . LL(1) .
17. LL(1) . .
, LL(1), LL(1)- . .
P → begin D; end
D → d, D
D → d
→ s;
→ s
, ( ) , . , . LL(1)-:
P → begin D; end
D → d X ( X)
X →, D ( 1- D d , D)
X → ε ( 2- D d ( ))
→ s Y ( Y)
Y →; ( 1- C s ; C)
Y → ε ( 2- C s ( ))
,
S → aSb
S → aSc
S → ε
S → aSX
S → ε
X → b
X → c
LL(1). , , , . , .
1. P → Qx
2. P → Ry
3. Q → sQm
4. Q → q
5. R → sRn
6. R → r
P s, , " s ", Q R 1 2:
P → sQmx
P → sRny
P → qx
P → ry
:
P → qx
P → ry
P → sP 1
P 1 → Qmx
P 1 → Rny
P1 P . , P:
P 1 → sQmmx
P 1 → qmx
P 1 → sRnny
P 1 → rny
,
P 1 → qmx
P 1 → rny
P 1 → sP 2
P 2 → Qmmx
P 2 → Rnny
P2 P1 P, , , . , , LL(1)-.