#include "closing.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
int n, x, y, ch[202020], ans;
ll k, need[202020], dis[202020];
vector< pair<int, ll> > adj[202020];
priority_queue<pll> pq;
int L;
vector< pair<int, ll> > path;
void find_path(int v) {
for (int i = 0; i < adj[v].size(); i++) {
if (path.back().first == y) return;
int u = adj[v][i].first; ll w = adj[v][i].second;
if (ch[u] == 1) continue;
ch[u] = 1;
path.push_back({u, w});
find_path(u);
if (path.back().first != y) path.pop_back();
}
}
int cnt = 0, visit[202020];
int not_intersect(int l, int r) {
while (!pq.empty()) pq.pop();
pq.push({-0, x});
pq.push({-0, y});
while (!pq.empty()) {
int v = pq.top().second; ll w = -pq.top().first;
pq.pop();
if (k - w >= 0) {
cnt++;
k -= w;
}
else break;
visit[v] = 1;
for (int i = 0; i < (int)adj[v].size(); i++) {
if (visit[adj[v][i].first] == 1) continue;
if (v == l && adj[v][i].first == r) continue;
if (v == r && adj[v][i].first == l) continue;
pq.push({-w-adj[v][i].second, adj[v][i].first});
}
}
return cnt;
}
pair<int, ll> in[3030][3030];
void inner() {
for (int r = 0; r <= L; r++) {
in[r][L].first = r + 2;
in[r][L].second = 0;
ll need[3030];
for (int i = 0; i <= r; i++) need[i] = dis[i] - dis[0];
for (int i = r + 1; i <= L; i++) need[i] = 0;
for (int i = 0; i <= L; i++) in[r][L].second += need[i];
for (int l = L - 1; l >= 0; l--) {
in[r][l].first = in[r][l + 1].first + 1;
in[r][l].second = in[r][l + 1].second + max(0LL, dis[L] - dis[l] - need[l]);
}
}
}
ll dp[404040], nxt[404040];
void update(ll a, ll b) {
for (int i = 0; i <= 2*n; i++) {
ll val = dp[i];
if (i >= 1) val = min(val, dp[i - 1] + a);
if (i >= 2) val = min(val, dp[i - 2] + b);
nxt[i] = val;
}
for (int i = 0; i <= 2*n; i++) dp[i] = nxt[i];
}
void DFS(int v, ll a, ll b) {
for (int i = 0; i < adj[v].size(); i++) {
int u = adj[v][i].first; ll w = adj[v][i].second;
if (ch[u] == 1) continue;
ch[u] = 1;
update(a + w, b + w);
DFS(u, a + w, b + w);
}
}
void outer(int r, int l) {
for (int i = 0; i < n; i++) ch[i] = 0;
for (int i = 0; i <= L; i++) ch[path[i].first] = 1;
for (int i = 0; i <= 2*n; i++) dp[i] = 2e18;
dp[0] = 0;
/*
for (int i = 0; i <= r; i++) {
ll a = min(dis[i] - dis[0], dis[L] - dis[i]);
ll b = max(dis[i] - dis[0], dis[L] - dis[i]);
DFS(path[i].first, a, b);
}
for (int i = l; i <= L; i++) {
ll a = min(dis[i] - dis[0], dis[L] - dis[i]);
ll b = max(dis[i] - dis[0], dis[L] - dis[i]);
DFS(path[i].first, a, b);
}
*/
if (r < l) {
for (int i = 0; i <= r; i++) {
DFS(path[i].first, dis[i] - dis[0], 2e18);
}
for (int i = l; i <= L; i++) {
DFS(path[i].first, dis[L] - dis[i], 2e18);
}
}
else {
for (int i = 0; i <= l - 1; i++) {
DFS(path[i].first, dis[i] - dis[0], 2e18);
}
for (int i = l; i <= r; i++) {
ll a = min(dis[i] - dis[0], dis[L] - dis[i]);
ll b = max(dis[i] - dis[0], dis[L] - dis[i]);
DFS(path[i].first, a, b);
}
for (int i = r + 1; i <= L; i++) {
DFS(path[i].first, dis[L] - dis[i], 2e18);
}
}
}
int max_score(int N, int X, int Y, ll K, vector<int> U, vector<int> V, vector<int> W) {
n = N, x = X, y = Y, k = K;
ans = 0;
for (int i = 0; i < n; i++) adj[i].clear();
path.clear();
for (int i = 0; i < (int)U.size(); i++) {
adj[U[i]].push_back({V[i], W[i]});
adj[V[i]].push_back({U[i], W[i]});
}
for (int i = 0; i < n; i++) ch[i] = 0;
path.push_back({x, 0});
ch[x] = 1;
find_path(x);
assert(path.back().first == y);
L = path.size() - 1;
for (int i = 1; i <= L; i++) dis[i] = dis[i - 1] + path[i].second;
int midp = 0;
for (int i = 0; i <= L; i++) {
if (dis[i] - dis[0] > dis[L] - dis[i]) {
midp = i;
break;
}
}
ans = not_intersect(path[midp - 1].first, path[midp].first);
return ans;
inner();
for (int r = 0; r <= L; r++) {
for (int l = L; l >= 0; l--) {
if (k - in[r][l].second < 0) continue;
int val = in[r][l].first;
outer(r, l);
int idx = upper_bound(dp, dp + 2*n + 1, k - in[r][l].second) - dp - 1;
ans = max(ans, val + idx);
}
}
return ans;
}
Compilation message
closing.cpp: In function 'void find_path(int)':
closing.cpp:15:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
15 | for (int i = 0; i < adj[v].size(); i++) {
| ~~^~~~~~~~~~~~~~~
closing.cpp: In function 'int not_intersect(int, int)':
closing.cpp:42:9: error: reference to 'visit' is ambiguous
42 | visit[v] = 1;
| ^~~~~
In file included from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:133,
from closing.cpp:2:
/usr/include/c++/10/variant:1700:5: note: candidates are: 'template<class _Visitor, class ... _Variants> constexpr decltype(auto) std::visit(_Visitor&&, _Variants&& ...)'
1700 | visit(_Visitor&& __visitor, _Variants&&... __variants)
| ^~~~~
closing.cpp:26:14: note: 'int visit [202020]'
26 | int cnt = 0, visit[202020];
| ^~~~~
closing.cpp:44:17: error: reference to 'visit' is ambiguous
44 | if (visit[adj[v][i].first] == 1) continue;
| ^~~~~
In file included from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:133,
from closing.cpp:2:
/usr/include/c++/10/variant:1700:5: note: candidates are: 'template<class _Visitor, class ... _Variants> constexpr decltype(auto) std::visit(_Visitor&&, _Variants&& ...)'
1700 | visit(_Visitor&& __visitor, _Variants&&... __variants)
| ^~~~~
closing.cpp:26:14: note: 'int visit [202020]'
26 | int cnt = 0, visit[202020];
| ^~~~~
closing.cpp: In function 'void DFS(int, ll, ll)':
closing.cpp:81:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
81 | for (int i = 0; i < adj[v].size(); i++) {
| ~~^~~~~~~~~~~~~~~
