| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 962549 | tutis | 봉쇄 시간 (IOI23_closing) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "closing.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
int max_score(int N, int X, int Y, long long K,
vector<int> U, vector<int> V, vector<int> W) {
vector <pair<int, int>> adj[N];
vector <vector<int>> adj1[2];
adj1[0] = vector<int>(N);
adj1[1] = vector<int>(N);
for (int i = 0; i < N - 1; i++) {
adj[U[i]].push_back({V[i], W[i]});
adj[V[i]].push_back({U[i], W[i]});
}
vector <ll> D[2];
D[0] = vector<ll>(N);
D[1] = vector<ll>(N);
int XY[2] = {X, Y};
vector<int> x2y;
for (int t: {0, 1}) {
D[t][XY[t]] = 0;
vector<int> P;
function<void(int, int)> dfs = [&](int i, int p) -> void {
if (p != -1) {
adj1[t][p].push_back(i);
}
P.push_back(i);
if (t == 0 && i == Y) {
x2y = P;
}
for (auto j: adj[i]) {
if (j.first == p) {
continue;
}
D[t][j.first] = D[t][i] + j.second;
dfs(j.first, i);
}
P.pop_back();
};
dfs(XY[t], -1);
}
int ret = 0;
vector <ll> cost[2];
for (int t: {0, 1}) {
ll sum = 0;
priority_queue <pair<int, int>> Q;
Q.push({0, XY[t]});
while (!Q.empty()) {
int i = Q.top().second;
sum += D[t][i];
cost[t].push_back(sum);
if (sum > K) {
break;
}
for (auto j: adj1[t][i]) {
Q.push({-D[t][j], j});
}
}
}
for (int i = 0; i < cost[0].size(); i++) {
for (int j = 0; j < cost[1].size(); j++) {
if (cost[0][i] + cost[1][j] <= K) {
ret = max(ret, i + 1 + j + 1);
}
}
}
int m = 0;
while (m + 1 < x2y.size() && D[0][x2y[m + 1]] <= D[1][x2y[m + 1]]) {
m++;
}
ll s0 = 0;
ll s1 = 0;
for (int i = 0; i <= m; i++) {
s0 += D[0][x2y[i]];
s0 = min(s, K + 1);
}
for (int j = x2y.size() - 1; j > m; j--) {
s1 += D[1][x2y[j]];
s1 = min(s, K + 1);
}
if (s0 + s1 > K) {
return ret;
}
return ret;
}