int main () {
// example expression: (true and x) or (y and (not x))
BooleanExp* expression;
Context context;
VariableExp* x = new VariableExp("X");
VariableExp* y = new VariableExp("Y");
expression = new OrExp(new AndExp(new Constant(true), x), new AndExp(y, new NotExp(x)));
context.Assign(x, false);
context.Assign(y, true);
bool result = expression->Evaluate(context);
VariableExp* z = new VariableExp("Z");
NotExp not_z(z);
BooleanExp* replacement = expression->Replace("Y", not_z);
context.Assign(z, true);
result = replacement->Evaluate(context);
return 0;
}
main () {
/*
*/
BooleanExp* expression;
Context context;
VariableExp* x = new VariableExp("X");
VariableExp* y = new VariableExp("Y");
expression = new OrExp(
new AndExp(new Constant(true), x),
new AndExp(y, new NotExp(x))
);
/*
*/
context.Assign(x, false);
context.Assign(y, true);
bool result = expression->Evaluate(context);
/*
*/
BooleanExp* replacement;
VariableExp* z = new VariableExp("Z");
replacement = new NotExp(z);
expression->Replace("Y", *replacement);
context.Assign(z, true);
result = expression ->Evaluate(context);
/*
*/
}
BooleanExp* AndExp::Replace (const char* name, BooleanExp& exp) {
return
new AndExp(
_operand1->Replace(name, exp),
_operand2->Replace(name, exp)
);
}
int main(int argc, char ** argv)
{
BooleanExp *expression;
Context context;
VariableExp* x = new VariableExp("X");
VariableExp* y = new VariableExp("Y");
expression = new OrExp(
new AndExp(new Constant(true),x),
new AndExp(y,new NotExp(x)));
context.Assign(x,false);
context.Assign(y,true);
bool result = expression->Evaluate(context);
char *str;
if(result == true)
str = "true";
else
str = "false";
printf("result is %s\n",str);
system("pause");
return 0;
}
BooleanExp* AndExp::Copy () const {
return
new AndExp(_operand1->Copy(), _operand2->Copy());
}
bool AndExp::Evaluate (Context& aContext) {
return
_operand1->Evaluate(aContext) &&
_operand2->Evaluate(aContext);
}