1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
|
id = 177
number = 20
visible = False
facts = None
solution = '''\
algol_if(fun(S0,S,apply177([printout=[]|S0],S,Minstructs))) -->
[begin], instructs177(Minstructs), [end].
instructs177(Minstr) --> instr177(Minstr).
instructs177(fun(S0,S,
(apply177(S0,S1,Minstr),
apply177(S1,S,Minstructs))))
-->
instr177(Minstr), instructs177(Minstructs).
instr177(Massign) --> assign177(Massign).
instr177(fun(S0,[printout = L1|S1],
(memb(X = V,S0),
del(printout = L0,S0,S1),
conc(L0,[V],L1))))
-->
[print(X)].
instr177(fun(S0,S,
loop177(S0,Mcond,Minstructs,S)))
-->
[while], cond177(Mcond), [do,begin], instructs177(Minstructs), [end].
instr177(fun(S0, S,
(apply177(S0, true, Mcond), !,
apply177(S0, S, MinstructsA)
;
apply177(S0, S, MinstructsB))))
-->
[if], cond177(Mcond), [then], instructs177(MinstructsA), [else], instructs177(MinstructsB), [end].
assign177(fun(S0,[X = Value|S1],
(apply177(S0,Value,Mexpr),
del(X = _,S0,S1))))
-->
var177(X), [:=], expr177(Mexpr).
cond177( fun( S, TruthVal,
(apply177(S,Val1,ME1),
apply177(S,Val2,ME2),
(Val1 < Val2,!,TruthVal = true ; TruthVal = false))))
-->
expr177(ME1), [<], expr177(ME2).
var177(X) --> [X], {atom(X)}.
expr177(fun(S,Value,eval(Expr,S,Value))) -->
[Expr].
apply177(In, Out, fun(In, Out, Goals)) :-
call(Goals).
loop177( State0, Mcond, _, State0) :-
apply177( State0, false, Mcond), !.
loop177( S0, Mcond, MBody, S) :-
copy_term( MBody, MBodyCopy),
apply177( S0, S1, MBody),
loop177( S1, Mcond, MBodyCopy, S).
eval177( N, _, N) :-
number177( N), !.
eval177( X, State, Val) :- % A program variable
atom( X), !,
memb( X = Val, State).
eval177( E1 + E2, State, Val) :- !,
eval177( E1, State, V1),
eval177( E2, State, V2),
Val is V1 + V2.
eval177( E1 - E2, State, Val) :- !,
eval177( E1, State, V1),
eval177( E2, State, V2),
Val is V1 - V2.
eval177( E1 * E2, State, Val) :- !,
eval177( E1, State, V1),
eval177( E2, State, V2),
Val is V1 * V2.
eval177( E1 / E2, State, Val) :- !,
eval177( E1, State, V1),
eval177( E2, State, V2),
Val is V1 / V2.
'''
|
