1. Connect jobs (P121 Exercise 1), to complete 4), 5) two steps.
S1--->#S#
S--->a | ^ | (T)
T--->T,S | S
1) calculating and FIRSTVT LASTVT.
2) find a three relationships right.
3) construction operator precedence table.
4) whether the operator priority to grammar?
5) given input string (a, (a, a)) # of operator precedence analysis.
| Stack |
relationship |
Input string |
action |
| # |
< |
(a,(a,a))# |
Moved into |
| #( |
< |
a,(a,a))# |
Moved into |
| #(a |
> |
,(a,a))# |
Reduction |
| #(N |
< |
,(a,a))# |
Moved into |
| #(N, |
< |
(a,a))# |
Moved into |
| #(N,( |
< |
a,a))# |
Moved into |
| #(N,( a |
> |
,a))# |
Reduction |
| #(N,( N, |
< |
a))# |
Moved into |
| #(N,( N, a |
> |
))# |
Reduction |
| #(N,( N, N |
> |
))# |
Reduction |
| #(N,( N |
= |
))# |
Moved into |
| #(N,(N) |
> |
)# |
Reduction |
| #(N,N |
> |
)# |
Reduction |
| #(N |
= |
)# |
Moved into |
| #(N) |
> |
# |
Reduction |
| # N |
= |
# |
Moved into |
| # N # |
|
|
|
2. Try parser written bottom-up.
Expression can be written only partially.
3. The following statement is given ternary type, quaternary style and Reverse Polish Notation.
a*b＋（c－d)／e
Three yuan type:
(1) (* a,b)
(2) (- c,d)
(3) (/ (2),e)
(4) (+ (1),(3))
Quaternion type:
(1) (* ,a,b,t1)
(2) (- ,c,d,t2)
(3) (/ ,t2,e,t3)
(4) (+ t1, t3, t4)
Reverse Polish Notation:
ab * cd-e / +