#include "werewolf.h"
#include <bits/stdc++.h>
using namespace std;
using ll = int;
#define F(i, l, r) for (ll i = (l); i < (r); ++i)
#define A(a) (a).begin(), (a).end()
using pl = pair<ll, ll>;
using vl = vector<ll>;
#define K first
#define V second
#define NN 200010
ll parent[NN];
vl dsuSet[NN];
ll find(ll i) {
while ( i - parent[i]) i = parent[i];
return i;
}
optional<pair<pl, vl>> merge(ll i, ll j) {
i = find(i), j = find(j);
if (i-j) {
if (dsuSet[i].size() < dsuSet[j].size()) swap(i, j);
parent[j] = i;
dsuSet[i].insert(dsuSet[i].end(), A(dsuSet[j]));
return {pair(pair(i, j), dsuSet[j])};
}
return {};
}
// another alternate form of the kruskal reconstruction tree
// We're trying to maintain, "does node E exists in my KRT subtree?"
// Hard to maintain with normal KRT.
// Instead, let's store in the event-KRT
namespace krt {
ll parent[NN];
map<ll, ll> nodesInSubtree[NN];
ll pw[NN];
ll find(ll i) {
while (i - parent[i]) i = parent[i];
return i;
}
void merge(ll i, ll j, ll w) {
i = find(i), j = find(j);
if (i-j) {
if (nodesInSubtree[i].size() < nodesInSubtree[j].size()) {
swap(i, j);
}
for (auto &[x, _]: nodesInSubtree[j]) nodesInSubtree[i][x] = w;
pw[j] = w;
parent[j] = i;
}
}
void init(ll n) {
F(i, 0, n) {
nodesInSubtree[i][i] = n-1; // this is sus
parent[i] = i;
}
}
void change(ll node, ll relabelFrom, ll relabelTo) {
// cout << "CHANGE " << endl;
// cout << "START NODE: " << node << " " << relabelFrom << " -> " << relabelTo << endl;
// for (auto [k, v]: nodesInSubtree[node]) cout << k << " " << v << " | "; cout << endl;
// This case happens when we relabel to the root for multiple nodes. In this case, we've already compressed the relabeling, so we're good.
// (Here is an example of a data structure where it's trivial to update things from bototm up, but hard to know what to dfs into top-down).
if (!nodesInSubtree[node].count(relabelFrom)) return;
// this is correct since we're just locally compressing the sequence, we're not doing anything fancy like passing up the time.
// in the brute force version, we'd maintain the entire sequence of relabeled nodes per thing.
// but obviously, we can compress all of those, and then only the maximum time (e.g. earliest suffix) matters.
ll v = nodesInSubtree[node][relabelFrom];
nodesInSubtree[node].erase(relabelFrom);
nodesInSubtree[node][relabelTo] = max(nodesInSubtree[node][relabelTo], v);
if (node != parent[node]) change(parent[node], relabelFrom, relabelTo);
}
// this is a bit... sus.
bool query(ll node, ll searchLabel, ll w) {
auto it = nodesInSubtree[node].find(searchLabel);
if (it != nodesInSubtree[node].end() and it->V >= w) return true;
if (node != parent[node] and pw[node] >= w) return query(parent[node], searchLabel, w);
return false;
}
}
std::vector<int> check_validity(int N, std::vector<int> X, std::vector<int> Y,
std::vector<int> S, std::vector<int> E,
std::vector<int> L, std::vector<int> R) {
ll Q = R.size();
vector<vector<pl>> queries(N);
std::vector<int> ans(Q);
F(i, 0, Q) {
queries[R[i]].emplace_back(L[i], i);
}
vector<vector<pl>> edges(N), edgesPre(N);
F(i, 0, X.size()) {
edges[max(X[i], Y[i])].emplace_back(X[i], Y[i]);
edgesPre[min(X[i], Y[i])].emplace_back(X[i], Y[i]);
}
// E means u can go from [L, N-1] in the suffix dSU
krt::init(N);
for (ll i = N-1; i >= 0; --i) for (auto [x, y]: edgesPre[i]) {
krt::merge(x, y, i);
}
// S means u can go from [0, R] in the prefix DSU
F(i, 0, N) {
parent[i] = i;
dsuSet[i] = {i};
}
F(right, 0, N) {
for (auto &[x, y]: edges[right]) {
auto result = merge(x, y);
if (result.has_value()) {
auto [relabel, nodes] = *result;
for (auto x: nodes) {
krt::change(x, relabel.V, relabel.K);
}
}
}
for (auto &[left, qidx]: queries[right]) {
ll queryLabel = find(S[qidx]);
ans[qidx] = krt::query(E[qidx], queryLabel, left);
}
}
return ans;
}
Compilation message
werewolf.cpp: In function 'std::vector<int> check_validity(int, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
werewolf.cpp:6:39: warning: comparison of integer expressions of different signedness: 'll' {aka 'int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
6 | #define F(i, l, r) for (ll i = (l); i < (r); ++i)
| ^
werewolf.cpp:113:5: note: in expansion of macro 'F'
113 | F(i, 0, X.size()) {
| ^
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
15964 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
15964 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2115 ms |
126468 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
3 ms |
15964 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
