#ifndef hwe
#include "highway.h"
#endif
#include <bits/stdc++.h>
using namespace std;
#define popcount(n) (__builtin_popcountll((n)))
#define clz(n) (__builtin_clzll((n)))
#define ctz(n) (__builtin_ctzll((n)))
#define lg(n) (63 - __builtin_clzll((n)))
#define BIT(n, i) (((n) >> (i)) & 1ll)
#define MASK(i) (1ll << (i))
#define FLIP(n, i) ((n) ^ (1ll << (i)))
#define ON(n, i) ((n) | MASK(i))
#define OFF(n, i) ((n) & ~MASK(i))
#define Int __int128
#define fi first
#define se second
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long long, int> pli;
typedef pair<int, long long> pil;
typedef vector<pair<int, int>> vii;
typedef vector<pair<long long, long long>> vll;
typedef vector<pair<long long, int>> vli;
typedef vector<pair<int, long long>> vil;
template <class T1, class T2>
bool maximize(T1 &x, T2 y) {
if (x < y) {
x = y;
return true;
}
return false;
}
template <class T1, class T2>
bool minimize(T1 &x, T2 y) {
if (x > y) {
x = y;
return true;
}
return false;
}
template <class T>
void remove_duplicate(vector<T> &ve) {
sort (ve.begin(), ve.end());
ve.resize(unique(ve.begin(), ve.end()) - ve.begin());
}
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
template <class T> T random(T l, T r) {
return uniform_int_distribution<T>(l, r)(rng);
}
template <class T> T random(T r) {
return rng() % r;
}
const int N = 90000 + 5;
const int MOD = 1e9 + 7;
const int inf = 1e9;
const ll INF = 1e18;
const int LIGHT = 0, HEAVY = 1;
int asked = 0, maxDepth, dep[N], e[N];
vii adj[N];
vector<int> ve[N];
map<vector<int>, ll> mem;
#ifdef hwe
namespace Grader {
int n, m, s, t;
ll dist[N];
pii edges[N];
vii adj[N];
vector<int> w;
void get() {
cin >> n >> m >> s >> t;
for (int i = 0; i < m; ++i) {
int u, v; cin >> u >> v;
adj[u].emplace_back(v, i), adj[v].emplace_back(u, i);
edges[i] = make_pair(u, v);
}
}
ll dijkstra(int s, int t) {
memset(dist, 0x0f, sizeof dist); dist[s] = 0;
priority_queue<pli, vli, greater<pli>> pq; pq.emplace(0, s);
while (!pq.empty()) {
int u = pq.top().se; pq.pop();
// cerr << "dijkstra " << u << ' ' << dist[u] << '\n';
for (auto [v, id] : adj[u]) if (minimize(dist[v], dist[u] + w[id])) {
pq.emplace(dist[v], v);
}
}
return dist[t];
}
ll ask(const vector<int> &_w) {
w = _w; for (auto &x : w) ++x;
return dijkstra(s, t);
}
}
ll ask(const vector<int> &w) {
return Grader::ask(w);
}
void answer(int s, int t) {
cerr << "Answer " << s << ' ' << t << '\n';
}
#endif
ll myask(const vector<int> &w) {
auto it = mem.find(w);
if (it != mem.end()) return it->se;
assert(++asked <= 60);
return mem[w] = ask(w);
}
void dfs(int u, int fa) {
maximize(maxDepth, dep[u]);
for (auto [v, id] : adj[u]) if (v != fa) {
dep[v] = dep[u] + 1, e[v] = id;
ve[dep[v]].emplace_back(v);
dfs(v, u);
}
}
void find_pair(int n, vector<int> U, vector<int> V, int A, int B) {
int m = U.size(); asked = 0;
for (int i = 0; i < m; ++i) {
adj[U[i]].emplace_back(V[i], i), adj[V[i]].emplace_back(U[i], i);
}
vector<int> w(m, LIGHT);
ll fixed = myask(w); int numEdges = fixed / A;
for (int i = 1; i < n; ++i) ve[i].clear();
dep[0] = maxDepth = 0; dfs(0, -1);
int low = 1, high = maxDepth, depthT = 0;
while (low <= high) {
int mid = low + high >> 1; vector<int> w(m, HEAVY);
for (int d = 1; d <= mid; ++d) for (auto v : ve[d]) {
w[e[v]] = LIGHT;
}
if (myask(w) == fixed) high = (depthT = mid) - 1;
else low = mid + 1;
}
low = 0, high = int(ve[depthT].size()) - 2; int posT = ve[depthT].size() - 1;
while (low <= high) {
int mid = low + high >> 1; vector<int> w(m, HEAVY);
for (int i = 0; i <= mid; ++i) w[e[ve[depthT][i]]] = LIGHT;
if (myask(w) < 1ll * numEdges * B) high = (posT = mid) - 1;
else low = mid + 1;
}
int T = ve[depthT][posT];
low = 0, high = depthT - 1; int depthLCA = -1;
while (low <= high) {
int mid = low + high >> 1; vector<int> w(m, HEAVY);
for (int d = mid; d <= depthT; ++d) for (auto v : ve[d]) {
w[e[v]] = LIGHT;
}
if (myask(w) == fixed) low = (depthLCA = mid) + 1;
else high = mid - 1;
}
int depthS = numEdges - (depthT - depthLCA) + depthLCA;
for (int i = 1; i < n; ++i) ve[i].clear();
dep[T] = 0; dfs(T, -1);
low = 0, high = int(ve[depthS].size()) - 1; int posS = ve[depthS].size() - 1;
while (low <= high) {
int mid = low + high >> 1; vector<int> w(m, HEAVY);
for (int i = 0; i <= mid; ++i) w[e[ve[depthS][i]]] = LIGHT;
// cerr << mid << ' ' << myask(w) << '\n';
if (myask(w) < 1ll * numEdges * B) high = (posS = mid) - 1;
else low = mid + 1;
}
int S = ve[depthS][posS];
answer(S, T);
}
#ifdef hwe
signed main() {
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#ifdef hwe
freopen("input.inp", "r", stdin);
freopen("output.out", "w", stdout);
#else
#define taskname ""
if (fopen(taskname".inp", "r")) {
freopen(taskname".inp", "r", stdin);
freopen(taskname".out", "w", stdout);
}
#endif
Grader::get();
int n = Grader::n; vector<int> U, V;
for (int i = 0; i < Grader::m; ++i) {
int u, v; tie(u, v) = Grader::edges[i];
U.emplace_back(u), V.emplace_back(v);
}
find_pair(n, U, V, 1, 2);
cerr << '\n'; return 0;
}
#endif
Compilation message
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:153:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
153 | int mid = low + high >> 1; vector<int> w(m, HEAVY);
| ~~~~^~~~~~
highway.cpp:163:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
163 | int mid = low + high >> 1; vector<int> w(m, HEAVY);
| ~~~~^~~~~~
highway.cpp:172:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
172 | int mid = low + high >> 1; vector<int> w(m, HEAVY);
| ~~~~^~~~~~
highway.cpp:186:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
186 | int mid = low + high >> 1; vector<int> w(m, HEAVY);
| ~~~~^~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
4688 KB |
Output is incorrect: {s, t} is wrong. |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
4688 KB |
Output is incorrect: {s, t} is wrong. |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
14 ms |
7456 KB |
Output is incorrect: {s, t} is wrong. |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
2 ms |
4688 KB |
Output is incorrect: {s, t} is wrong. |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
69 ms |
33476 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
63 ms |
33608 KB |
Execution killed with signal 6 |
| 2 |
Halted |
0 ms |
0 KB |
- |
