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#include "../util.h"
#pragma GCC diagnostic ignored "-Wshadow"
#include <datastructures/LCT.cpp>
struct Naive {
vector<set<int>> adj;
vector<ll> weight;
Naive(int n) : adj(n), weight(n, queryDefault) {}
pair<ll, bool> dfs_path(int from, int to, ll delta = queryDefault, int prev = -1) {
if (from == to) {
weight[from] += delta;
return {weight[from], true};
}
for (int x : adj[from]) {
if (x == prev) continue;
auto [res, seen] = dfs_path(x, to, delta, from);
if (seen) {
weight[from] += delta;
return {res + weight[from], true};
}
}
return {queryDefault, false};
}
bool connected(int x, int y) {
return dfs_path(x, y).second;
}
void link(int x, int y) {
adj[x].insert(y);
adj[y].insert(x);
}
void cut(int x, int y) {
adj[x].erase(y);
adj[y].erase(x);
}
int lca(int root, int a, int b) {
int res = -1;
auto dfs_lca = [&](auto&& self, int c, int prev = -1) -> pair<bool, bool>{
bool seenA = c == a;
bool seenB = c == b;
for (int x : adj[c]) {
if (x == prev) continue;
auto [tmpA, tmpB] = self(self, x, c);
seenA |= tmpA;
seenB |= tmpB;
}
if (seenA && seenB && res < 0) res = c;
return {seenA, seenB};
};
dfs_lca(dfs_lca, root);
return res;
}
ll query(int from, int to) {
return dfs_path(from, to).first;
}
void modify(int from, int to, ll delta) {
dfs_path(from, to, delta);
}
int random(int x) {
vector<int> seen;
auto dfs_comp = [&](auto&& self, int c, int prev = -1) -> void {
seen.push_back(c);
for (int x : adj[c]) {
if (x == prev) continue;
self(self, x, c);
}
};
dfs_comp(dfs_comp, x);
return seen[Random::integer<int>(sz(seen))];
}
int randomAdj(int x) {
if (adj[x].empty()) return -1;
vector<int> seen(all(adj[x]));
return seen[Random::integer<int>(sz(seen))];
}
};
void stress_test() {
ll queries = 0;
ll connected = 0;
ll link = 0;
ll lca = 0;
ll sum = 0;
ll modify = 0;
ll cut = 0;
for (int tries = 0; tries < 500; tries++) {
int n = Random::integer<int>(1, 100);
int m = Random::integer<int>(100, 10'000);
LCT lct(n);
Naive naive(n);
for (int i = 0; i < m; i++) {
bool testConnected = Random::integer<int>(2) == 0;
bool testLink = Random::integer<int>(2) == 0;
bool testLCA = Random::integer<int>(2) == 0;
bool testSum = Random::integer<int>(2) == 0;
bool testModify = Random::integer<int>(2) == 0;
bool testCut = Random::integer<int>(2) == 0;
{
int a = Random::integer<int>(0, n);
int b = Random::integer<int>(0, n);
auto expected = naive.connected(a, b);
if (testConnected) {
connected++;
auto got = lct.connected(&lct.nodes[a], &lct.nodes[b]);
if (got != expected) cerr << "error: 1" << FAIL;
}
if (!expected && testLink) {
lct.link(&lct.nodes[a], &lct.nodes[b]);
naive.link(a, b);
link++;
expected = true;
}
if (testLCA && expected) {
int c = naive.random(a);
lct.makeRoot(&lct.nodes[c]);
auto gotLCA = lct.lca(&lct.nodes[a], &lct.nodes[b])->id;
auto expectedLCA = naive.lca(c, a, b);
if (gotLCA != expectedLCA) cerr << "error: 2" << FAIL;
lca++;
}
if (testSum && expected) {
auto gotSum = lct.query(&lct.nodes[a], &lct.nodes[b]);
auto expectedSum = naive.query(a, b);
if (gotSum != expectedSum) cerr << "error: 3" << FAIL;
sum++;
}
if (testModify && expected) {
ll w = Random::integer<ll>(-1000, 1000);
lct.modify(&lct.nodes[a], &lct.nodes[b], w);//must a and b directly connected??
naive.modify(a, b, w);
modify++;
}
}
{
int a = Random::integer<int>(0, n);
int b = naive.randomAdj(a);
if (b >= 0 && testCut) {
lct.cut(&lct.nodes[a], &lct.nodes[b]);
naive.cut(a, b);
cut++;
}
}
queries++;
}
}
cerr << "tested random queries: " << queries << endl;
cerr << " connected: " << connected << endl;
cerr << " link: " << link << endl;
cerr << " lca: " << lca << endl;
cerr << " sum: " << sum << endl;
cerr << " modify: " << modify << endl;
cerr << " cut: " << cut << endl;
}
constexpr int N = 200'000;
constexpr int M = 500'000;
void performance_test() {
timer t;
t.start();
LCT lct(N);
t.stop();
hash_t hash = 0;
for (int operations = 0; operations < N; operations++) {
int a = Random::integer<int>(0, N);
int b = Random::integer<int>(0, N);
ll w = Random::integer<ll>(-1000, 1000);
t.start();
if (!lct.connected(&lct.nodes[a], &lct.nodes[b])) {
lct.link(&lct.nodes[a], &lct.nodes[b]);
}
lct.modify(&lct.nodes[a], &lct.nodes[b], w);
hash += lct.query(&lct.nodes[a], &lct.nodes[b]);
t.stop();
}
if (t.time > 500) cerr << "too slow: " << t.time << FAIL;
cerr << "tested performance: " << t.time << "ms (hash: " << hash << ")" << endl;
}
int main() {
stress_test();
if (!sanitize) performance_test();
}
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