leetcode

Solution to some Leetcode problems written in C++
git clone git://git.dimitrijedobrota.com/leetcode.git
Log | Files | Refs | README | LICENSE |
commit631b49f2e2031626a19f7c9e74f1294ed84cb4bb
parentc2b48d325baa1eb01391be3ad89a1f7b5891f94b
authorDimitrije Dobrota <mail@dimitrijedobrota.com>
dateSun, 29 Sep 2024 09:49:05 +0200

Daily Problem

Diffstat:
AProblems/0432.cpp|+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
MREADME.md|+

2 files changed, 83 insertions(+), 0 deletions(-)

diff --git a/Problems/0432.cpp b/Problems/0432.cpp

@@ -0,0 +1,82 @@

class AllOne {
struct Node {
int freq = 0;
Node *prev = nullptr;
Node *next = nullptr;
unordered_set<string> keys;
};
unordered_map<string, Node *> map;
Node head = {0, nullptr, &tail};
Node tail = {0, &head, nullptr};
public:
void inc(const string &key) {
if (map.find(key) != map.end()) {
Node *node = map[key];
int freq = node->freq;
node->keys.erase(key);
Node *nnode = node->next;
if (nnode == &tail || nnode->freq != freq + 1) {
map[key] = node->next = nnode->prev = new Node(freq + 1, node, nnode, {key});
} else {
nnode->keys.insert(key);
map[key] = nnode;
}
if (node->keys.empty()) {
removeNode(node);
}
} else {
Node *firstNode = head.next;
if (firstNode == &tail || firstNode->freq > 1) {
map[key] = head.next = firstNode->prev = new Node(1, &head, firstNode, {key});
} else {
firstNode->keys.insert(key);
map[key] = firstNode;
}
}
}
void dec(const string &key) {
if (map.find(key) == map.end()) {
return;
}
Node *node = map[key];
node->keys.erase(key);
int freq = node->freq;
if (freq == 1) {
map.erase(key);
} else {
Node *pnode = node->prev;
if (pnode == &head || pnode->freq != freq - 1) {
map[key] = pnode->next = node->prev = new Node(freq - 1, pnode, node, {key});
} else {
pnode->keys.insert(key);
map[key] = pnode;
}
}
if (node->keys.empty()) {
removeNode(node);
}
}
string getMaxKey() const { return tail.prev == &head ? "" : *(tail.prev->keys.begin()); }
string getMinKey() const { return head.next == &tail ? "" : *(head.next->keys.begin()); }
private:
void removeNode(Node *node) {
Node *pnode = node->prev;
Node *nnode = node->next;
pnode->next = nnode;
nnode->prev = pnode;
delete node;
}
};

diff --git a/README.md b/README.md

@@ -329,6 +329,7 @@ for solving problems.

| 0427 | Medium | [Construct Quad Tree](Problems/0427.cpp) |
| 0429 | Medium | [N-ary Tree Level Order Traversal](Problems/0429.cpp) |
| 0430 | Medium | [Flatten a Multilevel Doubly Linked list](Problems/0430.cpp) |
| 0432 | Hard | [All O`one Data Structure](Problems/0432.cpp) |
| 0433 | Medium | [Minimum Genetic Mutation](Problems/0433.cpp) |
| 0435 | Medium | [Non-overlapping Intervals](Problems/0435.cpp) |
| 0436 | Medium | [Find Right Interval](Problems/0436.cpp) |