void AVLDict::balance(node *& x){
if( x == NULL ) return;
int b = height(x->left) - height(x->right);
if( b >= -1 && b <= 1 ) return;
if( b == 2 ) {
if( height(x->left->left) > height(x->left->right) ) {
rotate_left(x);
} else {
double_rotate_left(x);
}
} else {
if( height(x->right->right) > height(x->right->left) ) {
rotate_right(x);
} else {
double_rotate_right(x);
}
}
}
static void fviol_(bst& b, node* A) {
if(!A) {
return;
}
fviol_(b, A->left);
fviol_(b, A->right);
std::pair<int, bool> left_depth = depth(A->left);
std::pair<int, bool> right_depth = depth(A->right);
if(std::abs(left_depth.first - right_depth.first) > 1) { //imbalance
if(left_depth.first > right_depth.first) { //left subtree
if(left_depth.second) { //left child
node* k1 = A;
node* k2 = A->left;
std::cout << "Left-Left: Performing left child single rotate on subtree: " << print(A) << " with k1=" << k1->data << " k2=" << k2->data << std::endl;
single_rotate_left(b, k1, k2);
}
else { //right child
node* k1 = A->left;
node* k2 = k1->right;
node* k3 = A;
std::cout << "Left-Right: Performing right child double rotate on subtree: " << print(A) << " with k1=" << k1->data << " k2=" << k2->data << " k3=" << k3->data << std::endl;
double_rotate_right(b, k1, k2, k3);
}
}
else { //right subtree
if(right_depth.second) { //left child
node* k1 = A->right;
node* k2 = k1->left;
node* k3 = A;
std::cout << "Right-Left: Performing left child double rotate on subtree: " << print(A) << " with k1=" << k1->data << " k2=" << k2->data << " k3=" << k3->data << std::endl;
double_rotate_left(b, k1, k2, k3);
}
else { //right child
node* k1 = A;
node* k2 = A->right;
std::cout << "Right-Right: Performing right child single rotate on subtree: " << print(A) << " with k1=" << k1->data << " k2=" << k2->data << std::endl;
single_rotate_right(b, k1, k2);
}
}
}
}