//Create a tree with the given data, left subtree, and right subtree then return the tree.
//O(1)
struct tree *createTree(int data, struct tree *left, struct tree *right){
//create the root
struct tree *root;
root=malloc(sizeof(struct tree));
//Assign that data and pointers of the new tree
root->data=data;
root->right=right;
root->left=left;
root->parent=NULL;
//If the right and left parents are not NULL, the left and right nodes came from another tree, and need to be detatched before adding to our tree
if(right!=NULL){
detatch(right);
root->right->parent=root;
}
if(left!=NULL){
detatch(left);
root->left->parent=root;
}
return root;
}
void irept::move_to_sub(irept &irep)
{
#ifdef SHARING
detatch();
#endif
get_sub().push_back(get_nil_irep());
get_sub().back().swap(irep);
}
void irept::move_to_named_sub(const irep_namet &name, irept &irep)
{
#ifdef SHARING
detatch();
#endif
add(name).swap(irep);
irep.clear();
}
//Assings the right subtree of the given node to the given right subtree
//O(1)
void setRight(struct tree *root, struct tree *right){
assert(root!=NULL);
//If the root's right is not null, we need to set it's parent pointer to null so it can be reassigned
if(root->right!=NULL)
root->right->parent=NULL;
//Now we can set the root's left subtree to the given left, and make sure it is not attatched to some other tree
root->right=right;
detatch(right);
}
//moves person of id x to to district i, j
int gw_move(GW g, int x, int i, int j) {
if(x >= g->pop) {
return 0;
}
PERSON *p = &(g->people[x]);
DISCT *from = &(g->grid[p->r][p->c]);
DISCT *to = &(g->grid[i][j]);
if(p->isAlive == 0) {
return 0;
}
detatch(from, p); //remove from current district
p->r = i;
p->c = j;
add(to, p); // add to new district
to->pop++; // increase population of new district
return 1;
}
//kill the person with id x
int gw_kill(GW g, int x) {
PERSON *p = &(g->people[x]);
if(p->isAlive == 0) {
return 0;
}
detatch(&(g->grid[p->r][p->c]), p);
if(g->dead == NULL) {
p->next = NULL;
}
else {
p->next = g->dead;
}
p->prev = NULL;
g->dead = p;
p->isAlive = 0;
g->pop--;
return 1;
}
