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package aterm.test;
import java.util.List;
import aterm.AFun;
import aterm.ATerm;
import aterm.ATermAppl;
import aterm.ATermFactory;
import aterm.pure.PureFactory;
public class TestFibInterpreted {
private ATermFactory factory;
private AFun zero, suc, plus, fib;
private ATermAppl tzero;
private ATerm fail;
private ATerm lhs[];
private ATerm rhs[];
public final static void main(String[] args) {
TestFibInterpreted t = new TestFibInterpreted(new PureFactory());
t.initRules();
t.test1(5);
}
public TestFibInterpreted(ATermFactory factory) {
this.factory = factory;
zero = factory.makeAFun("zero", 0, false);
suc = factory.makeAFun("suc", 1, false);
plus = factory.makeAFun("plus", 2, false);
fib = factory.makeAFun("fib", 1, false);
tzero = factory.makeAppl(zero);
fail = factory.parse("fail");
}
public void initRules() {
lhs = new ATerm[10];
rhs = new ATerm[10];
int ruleNumber = 0;
// fib(zero) -> suc(zero)
lhs[ruleNumber] = factory.parse("fib(zero)");
rhs[ruleNumber] = factory.parse("suc(zero)");
ruleNumber++;
// fib(suc(zero)) -> suc(zero)
lhs[ruleNumber] = factory.parse("fib(suc(zero))");
rhs[ruleNumber] = factory.parse("suc(zero)");
ruleNumber++;
// fib(suc(suc(X))) -> plus(fib(X),fib(suc(X)))
lhs[ruleNumber] = factory.parse("fib(suc(suc(<term>)))");
rhs[ruleNumber] = factory.parse("plus(fib(<term>),fib(suc(<term>)))");
ruleNumber++;
// plus(zero,X) -> X
lhs[ruleNumber] = factory.parse("plus(zero,<term>)");
rhs[ruleNumber] = factory.parse("<term>");
ruleNumber++;
// plus(suc(X),Y) -> plus(X,suc(Y))
lhs[ruleNumber] = factory.parse("plus(suc(<term>),<term>)");
rhs[ruleNumber] = factory.parse("plus(<term>,suc(<term>))");
ruleNumber++;
// congruence (suc)
lhs[ruleNumber] = factory.parse("suc(<term>)");
rhs[ruleNumber] = factory.parse("suc(<term>)");
ruleNumber++;
// congruence (plus)
lhs[ruleNumber] = factory.parse("plus(<term>,<term>)");
rhs[ruleNumber] = factory.parse("plus(<term>,<term>)");
ruleNumber++;
}
public ATerm oneStep(ATerm subject) {
int ruleNumber = 0;
List<Object> list;
// fib(zero) -> suc(zero)
list = subject.match(lhs[ruleNumber]);
if (list != null) {
return rhs[ruleNumber];
}
ruleNumber++;
// fib(suc(zero)) -> suc(zero)
list = subject.match(lhs[ruleNumber]);
if (list != null) {
return rhs[ruleNumber];
}
ruleNumber++;
// fib(suc(suc(X))) -> plus(fib(X),fib(suc(X)))
list = subject.match(lhs[ruleNumber]);
if (list != null) {
ATerm X = (ATerm) list.get(0);
list.add(X);
return factory.make(rhs[ruleNumber], list);
}
ruleNumber++;
// plus(zero,X) -> X
list = subject.match(lhs[ruleNumber]);
if (list != null) {
return factory.make(rhs[ruleNumber], list);
}
ruleNumber++;
// plus(suc(X),Y) -> plus(X,suc(Y))
list = subject.match(lhs[ruleNumber]);
if (list != null) {
return factory.make(rhs[ruleNumber], list);
}
ruleNumber++;
// congruence (suc)
list = subject.match(lhs[ruleNumber]);
if (list != null) {
//System.out.println("congsuc"); // applied 1184122 times fir fib(14)
ATerm X = (ATerm) list.get(0);
ATerm Xp = oneStep(X);
if (Xp.equals(fail)) {
return fail;
}
list.clear();
list.add(Xp);
return factory.make(rhs[ruleNumber], list);
}
ruleNumber++;
// congruence (plus)
list = subject.match(lhs[ruleNumber]);
if (list != null) {
//System.out.println("congplus"); // applied 9159 times fir fib(14)
ATerm X = (ATerm) list.get(0);
ATerm Xp = oneStep(X);
if (Xp.equals(fail)) {
ATerm Y = (ATerm) list.get(1);
ATerm Yp = oneStep(Y);
if (Yp.equals(fail)) {
return fail;
}
list.clear();
list.add(X);
list.add(Yp);
return factory.make(rhs[ruleNumber], list);
}
ATerm Y = (ATerm) list.get(1);
list.clear();
list.add(Xp);
list.add(Y);
return factory.make(rhs[ruleNumber], list);
}
ruleNumber++;
return fail;
}
public ATerm oneStepInnermost(ATerm subject) {
List<Object> list;
// fib(zero) -> suc(zero)
list = subject.match(lhs[0]);
if (list != null) {
return rhs[0];
}
// fib(suc(zero)) -> suc(zero)
list = subject.match(lhs[1]);
if (list != null) {
return rhs[1];
}
// fib(suc(suc(X))) -> plus(fib(X),fib(suc(X)))
list = subject.match(lhs[2]);
if (list != null) {
ATerm X = (ATerm) list.get(0);
ATerm X1 = normalize(factory.makeAppl(fib, X));
ATerm X2 = normalize(factory.makeAppl(fib, factory.makeAppl(suc, X)));
return factory.makeAppl(plus, X1, X2);
}
// plus(zero,X) -> X
list = subject.match(lhs[3]);
if (list != null) {
return (ATerm) list.get(0);
}
// plus(suc(X),Y) -> plus(X,suc(Y)))
list = subject.match(lhs[4]);
if (list != null) {
return factory.make(rhs[4], list);
}
return fail;
}
public ATerm normalize(ATerm t) {
ATerm s = t;
do {
t = s;
s = oneStep(t);
} while (!s.equals(fail));
return t;
}
public void test1(int n) {
ATermAppl N = tzero;
for (int i = 0; i < n; i++) {
N = factory.makeAppl(suc, N);
}
ATerm tfib = factory.makeAppl(fib, N);
normalize(tfib);
}
}