struct math_node *treeify(struct math_node **stack, int *size)
{
if (!stack || !size) { return 0; }
struct math_node *parent;
(*size)--;
parent = *(stack + *size);
if (*(parent->op) == '-' &&
*(parent->op + 1) >= 48 &&
*(parent->op + 1) <= 57) {
return parent;
}
if (isOperator(parent->op)) {
parent->right = treeify(stack, size);
parent->left = treeify(stack, size);
}
return parent;
}
int main()
{
int i;
char buffer[101];
struct math_node **stack;
int stack_size;
struct math_node *tree;
// get string
printf("Enter the postfix expression to be evaluated: ");
fgets(buffer, 100, stdin);
// stackify
stack = stackify(buffer, &stack_size);
// test stackify:
// printf("stack_size:%i\n", stack_size);
// for (i=0; i<stack_size; i++) {
// printf("%s\n", (*(stack + i))->op);
// }
// treeify
tree = treeify(stack, &stack_size);
// evaluate the tree
int value;
value = evaluate_tree(tree);
printf("The tree evaluates to: %d\n", value);
// print various forms
char* exp;
int length;
length = 0;
exp = getexp_prefix(tree, &length);
printf("Prefix Notation: %s\n", exp);
free(exp);
exp = 0;
length = 0;
exp = getexp_infix(tree, &length);
printf("Infix Notation: %s\n", exp);
free(exp);
exp = 0;
length = 0;
exp = getexp_postfix(tree, &length);
printf("Postfix Notation: %s\n", exp);
free(exp);
exp = 0;
// cleanup
tree_destructor(tree);
free(stack);
stack = 0;
return 0;
}
QueryOperator *
rewriteProvenanceComputation (ProvenanceComputation *op)
{
// for a sequence of updates of a transaction merge the sequence into a single
// query before rewrite.
if (op->inputType == PROV_INPUT_UPDATE_SEQUENCE
|| op->inputType == PROV_INPUT_TRANSACTION)
{
START_TIMER("rewrite - merge update reenactments");
mergeUpdateSequence(op);
STOP_TIMER("rewrite - merge update reenactments");
// need to restrict to updated rows?
if (op->inputType == PROV_INPUT_TRANSACTION
&& HAS_STRING_PROP(op,PROP_PC_ONLY_UPDATED))
{
START_TIMER("rewrite - restrict to updated rows");
restrictToUpdatedRows(op);
STOP_TIMER("rewrite - restrict to updated rows");
}
}
if (isRewriteOptionActivated(OPTION_TREEIFY_OPERATOR_MODEL))
{
treeify((QueryOperator *) op);
INFO_LOG("treeifyed operator model:\n\n%s", operatorToOverviewString((Node *) op));
DEBUG_LOG("treeifyed operator model:\n\n%s", beatify(nodeToString(op)));
ASSERT(isTree((QueryOperator *) op));
}
switch(op->provType)
{
case PROV_PI_CS:
if (isRewriteOptionActivated(OPTION_PI_CS_USE_COMPOSABLE))
return rewritePI_CSComposable(op);
else
return rewritePI_CS(op);
case PROV_TRANSFORMATION:
return rewriteTransformationProvenance((QueryOperator *) op);
}
return NULL;
}
