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authorGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
committerGloria Mundi <gloria@gloria-mundi.eu>2024-11-16 01:24:14 +0100
commit98567ec798aa8ca2cfbcb85c774dd470f30e30d4 (patch)
tree5113d5cc24d1ad5f93810b6442ce584a36950dc8 /content/datastructures/LCT.cpp
parentad3856a6b766087df0036de0b556f4700a6498c9 (diff)
parent8d11c6c8213f46f0fa19826917c255edd5d43cb1 (diff)
mzuenni tests
Diffstat (limited to 'content/datastructures/LCT.cpp')
-rw-r--r--content/datastructures/LCT.cpp178
1 files changed, 178 insertions, 0 deletions
diff --git a/content/datastructures/LCT.cpp b/content/datastructures/LCT.cpp
new file mode 100644
index 0000000..c1dd278
--- /dev/null
+++ b/content/datastructures/LCT.cpp
@@ -0,0 +1,178 @@
+constexpr ll queryDefault = 0;
+constexpr ll updateDefault = 0;
+
+ll _modify(ll x, ll y) {
+ return x + y;
+}
+
+ll _query(ll x, ll y) {
+ return x + y;
+}
+
+ll _update(ll delta, int length) {
+ if (delta == updateDefault) return updateDefault;
+ //ll result = delta
+ //for (int i=1; i<length; i++) result = _query(result, delta);
+ return delta * length;
+}
+
+//generic:
+ll joinValueDelta(ll value, ll delta) {
+ if (delta == updateDefault) return value;
+ return _modify(value, delta);
+}
+
+ll joinDeltas(ll delta1, ll delta2) {
+ if (delta1 == updateDefault) return delta2;
+ if (delta2 == updateDefault) return delta1;
+ return _modify(delta1, delta2);
+}
+
+struct LCT {
+ struct Node {
+ ll nodeValue, subTreeValue, delta;
+ bool revert;
+ int id, size;
+ Node *left, *right, *parent;
+
+ Node(int id = 0, int val = queryDefault) :
+ nodeValue(val), subTreeValue(val), delta(updateDefault),
+ revert(false), id(id), size(1),
+ left(nullptr), right(nullptr), parent(nullptr) {}
+
+ bool isRoot() {
+ return !parent || (parent->left != this &&
+ parent->right != this);
+ }
+
+ void push() {
+ if (revert) {
+ revert = false;
+ swap(left, right);
+ if (left) left->revert ^= 1;
+ if (right) right->revert ^= 1;
+ }
+ nodeValue = joinValueDelta(nodeValue, delta);
+ subTreeValue = joinValueDelta(subTreeValue,
+ _update(delta, size));
+ if (left) left->delta = joinDeltas(left->delta, delta);
+ if (right) right->delta = joinDeltas(right->delta, delta);
+ delta = updateDefault;
+ }
+
+ ll getSubtreeValue() {
+ return joinValueDelta(subTreeValue, _update(delta, size));
+ }
+
+ void update() {
+ subTreeValue = joinValueDelta(nodeValue, delta);
+ size = 1;
+ if (left) {
+ subTreeValue = _query(subTreeValue,
+ left->getSubtreeValue());
+ size += left->size;
+ }
+ if (right) {
+ subTreeValue = _query(subTreeValue,
+ right->getSubtreeValue());
+ size += right->size;
+ }}
+ };
+
+ vector<Node> nodes;
+
+ LCT(int n) : nodes(n) {
+ for (int i = 0; i < n; i++) nodes[i].id = i;
+ }
+
+ void connect(Node* ch, Node* p, int isLeftChild) {
+ if (ch) ch->parent = p;
+ if (isLeftChild >= 0) {
+ if (isLeftChild) p->left = ch;
+ else p->right = ch;
+ }}
+
+ void rotate(Node* x) {
+ Node* p = x->parent;
+ Node* g = p->parent;
+ bool isRootP = p->isRoot();
+ bool leftChildX = (x == p->left);
+
+ connect(leftChildX ? x->right : x->left, p, leftChildX);
+ connect(p, x, !leftChildX);
+ connect(x, g, isRootP ? -1 : p == g->left);
+ p->update();
+ }
+
+ void splay(Node* x) {
+ while (!x->isRoot()) {
+ Node* p = x->parent;
+ Node* g = p->parent;
+ if (!p->isRoot()) g->push();
+ p->push();
+ x->push();
+ if (!p->isRoot()) rotate((x == p->left) ==
+ (p == g->left) ? p : x);
+ rotate(x);
+ }
+ x->push();
+ x->update();
+ }
+
+ Node* expose(Node* x) {
+ Node* last = nullptr;
+ for (Node* y = x; y; y = y->parent) {
+ splay(y);
+ y->left = last;
+ last = y;
+ }
+ splay(x);
+ return last;
+ }
+
+ void makeRoot(Node* x) {
+ expose(x);
+ x->revert ^= 1;
+ }
+
+ bool connected(Node* x, Node* y) {
+ if (x == y) return true;
+ expose(x);
+ expose(y);
+ return x->parent;
+ }
+
+ void link(Node* x, Node* y) {
+ assert(!connected(x, y)); // not yet connected!
+ makeRoot(x);
+ x->parent = y;
+ }
+
+ void cut(Node* x, Node* y) {
+ makeRoot(x);
+ expose(y);
+ //must be a tree edge!
+ assert(!(y->right != x || x->left != nullptr));
+ y->right->parent = nullptr;
+ y->right = nullptr;
+ }
+
+ Node* lca(Node* x, Node* y) {
+ assert(connected(x, y));
+ expose(x);
+ return expose(y);
+ }
+
+ ll query(Node* from, Node* to) {
+ makeRoot(from);
+ expose(to);
+ if (to) return to->getSubtreeValue();
+ return queryDefault;
+ }
+
+ void modify(Node* from, Node* to, ll delta) {
+ makeRoot(from);
+ expose(to);
+ to->delta = joinDeltas(to->delta, delta);
+ }
+};