TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q) {
// swap p and q if p has a larger val.
if (p->val > q->val)
{
TreeNode* swap = p;
p = q;
q = swap;
}
bool p_isLeft = isUnder(root->left, p);
bool q_isRight = isUnder(root->right, q);
bool p_isRight = isUnder(root->right, p);
bool q_isLeft = isUnder(root->left, q);
// Is p left or myself?
// Is q right or myself?
// If both yes, then I am the LCA;
if ( (p_isLeft || (p == root)) && (q_isRight || (q == root)) )
return root;
// Are both p and q to the left? Then the LCA is somewhere under my left node.
if ( p_isLeft && q_isLeft )
return lowestCommonAncestor(root->left, p, q);
// Are both p and q to the right? Then the LCA is somewhere under my right node.
if ( p_isRight && q_isRight )
return lowestCommonAncestor(root->right, p, q);
}
bool isUnder(TreeNode* root, TreeNode* x) {
if (root == NULL)
return false;
if (
(root == x) ||
isUnder(root->left, x) ||
isUnder(root->right, x)
)
return true;
else
return false;
}
/**
* Update the massObject%'s position so that it lands on any baseable spriteObject%s that it may otherwise
* pass through in the tick.
*/
void massObject::checkPenetration()
{
for (vector<spriteObject*>::iterator it = sm->gameSprites.begin(); it != sm->gameSprites.end(); ++it)
{
if (*it == this || !(*it)->isBaseable())
continue;
if (inVertPlaneOf(*it) && isOver(*it))
{
y += vy;
if (isUnder(*it) || inHorizPlaneOf(*it))
{
y -= vy;
//round y off first
s16 rounds = y % 256;
y += rounds;
//adjust vertical velocity accordingly.
vy = (*it)->getTop() - getBottom();
vy = vy<<8;
} else {
y -= vy;
}
}
}
}
