Submission #1291507
Source Code Expand
#include <bits/stdc++.h>
using namespace std;
typedef long long int64;
const int INF = 1 << 30;
struct SegmentTree
{
vector< int > seg;
int sz;
SegmentTree(int n)
{
sz = 1;
while(sz < n) sz <<= 1;
seg.assign(2 * sz - 1, -INF);
}
void set(int k, int x)
{
seg[k + sz - 1] = x;
}
void build()
{
for(int k = sz - 2; k >= 0; k--) {
seg[k] = max(seg[2 * k + 1], seg[2 * k + 2]);
}
}
int rmq(int a, int b, int k, int l, int r)
{
if(a >= r || b <= l) return (-INF);
if(a <= l && r <= b) return (seg[k]);
return (max(rmq(a, b, 2 * k + 1, l, (l + r) >> 1),
rmq(a, b, 2 * k + 2, (l + r) >> 1, r)));
}
int rmq(int a, int b)
{
return (rmq(a, b, 0, 0, sz));
}
void update(int k, int x)
{
k += sz - 1;
seg[k] = x;
while(k > 0) {
k = (k - 1) >> 1;
seg[k] = max(seg[2 * k + 1], seg[2 * k + 2]);
}
}
};
vector< vector< int > > graph;
struct CentroidPathDecomposition
{
struct Centroid
{
int ParIndex, ParDepth, Deep;
vector< int > node;
inline int size()
{
return (node.size());
}
inline int &operator[](int k)
{
return (node[k]);
}
inline pair< int, int > Up()
{
return (make_pair(ParIndex, ParDepth));
}
};
vector< int > SubTreeSize, NextPath;
vector< int > TreeIndex, TreeDepth;
vector< Centroid > Centroids;
void BuildSubTreeSize()
{
stack< pair< int, int > > s;
s.push({0, -1});
while(!s.empty()) {
auto p = s.top();
s.pop();
if(~SubTreeSize[p.first]) {
NextPath[p.first] = -1;
for(auto &to : graph[p.first]) {
if(p.second == to) continue;
SubTreeSize[p.first] += SubTreeSize[to];
if(NextPath[p.first] == -1 || SubTreeSize[NextPath[p.first]] < SubTreeSize[to]) {
NextPath[p.first] = to;
}
}
} else {
s.push(p);
SubTreeSize[p.first] = 1;
for(auto &to : graph[p.first]) {
if(p.second != to) s.push({to, p.first});
}
}
}
}
void BuildPath()
{
stack< pair< int, int > > s;
Centroids.push_back((Centroid) {-1, -1, 0});
s.push({0, -1});
TreeIndex[0] = 0;
while(!s.empty()) {
auto p = s.top();
s.pop();
TreeDepth[p.first] = Centroids[TreeIndex[p.first]].size();
for(auto &to : graph[p.first]) {
if(p.second != to) {
if(to == NextPath[p.first]) { // Centroid-Path
TreeIndex[to] = TreeIndex[p.first];
} else { // Not Centroid-Path
TreeIndex[to] = Centroids.size();
Centroids.push_back((Centroid) {TreeIndex[p.first], TreeDepth[p.first], Centroids[TreeIndex[p.first]].Deep + 1});
}
s.push({to, p.first});
}
}
Centroids[TreeIndex[p.first]].node.push_back(p.first);
}
}
void AddEdge(int x, int y)
{
graph[x].push_back(y);
graph[y].push_back(x);
}
void Build()
{
BuildSubTreeSize();
BuildPath();
}
inline int size()
{
return (Centroids.size());
}
inline pair< int, int > Information(int idx)
{
return (make_pair(TreeIndex[idx], TreeDepth[idx]));
}
inline Centroid &operator[](int k)
{
return (Centroids[k]);
}
inline int LCA(int a, int b)
{
int TreeIdxA, TreeDepthA, TreeIdxB, TreeDepthB;
tie(TreeIdxA, TreeDepthA) = Information(a);
tie(TreeIdxB, TreeDepthB) = Information(b);
while(TreeIdxA != TreeIdxB) {
if(Centroids[TreeIdxA].Deep > Centroids[TreeIdxB].Deep) {
tie(TreeIdxA, TreeDepthA) = Centroids[TreeIdxA].Up();
} else {
tie(TreeIdxB, TreeDepthB) = Centroids[TreeIdxB].Up();
}
}
if(TreeDepthA > TreeDepthB) swap(TreeDepthA, TreeDepthB);
return (Centroids[TreeIdxA][TreeDepthA]);
}
CentroidPathDecomposition(int SZ)
{
graph.resize(SZ);
SubTreeSize.assign(SZ, -1);
NextPath.resize(SZ);
TreeIndex.resize(SZ);
TreeDepth.resize(SZ);
}
inline int getPathMax(int a, int b);
};
struct UnionFind
{
vector< int > data;
UnionFind(int sz) : data(sz, -1) {}
void unite(int x, int y)
{
x = find(x);
y = find(y);
if(x == y) return;
if(data[x] > data[y]) swap(x, y);
data[x] += data[y];
data[y] = x;
}
int find(int k)
{
if(data[k] < 0) return (k);
return (data[k] = find(data[k]));
}
};
struct edge
{
int u, v, cost;
bool operator<(const edge &e) const
{
return (cost < e.cost);
}
};
vector< SegmentTree > segs;
int CentroidPathDecomposition::getPathMax(int a, int b)
{
int TreeIdxA, TreeDepthA, TreeIdxB, TreeDepthB;
tie(TreeIdxA, TreeDepthA) = Information(a);
tie(TreeIdxB, TreeDepthB) = Information(b);
int ret = 0;
while(TreeIdxA != TreeIdxB) {
if(Centroids[TreeIdxA].Deep > Centroids[TreeIdxB].Deep) {
ret = max(ret, segs[TreeIdxA].rmq(0, TreeDepthA + 1));
tie(TreeIdxA, TreeDepthA) = Centroids[TreeIdxA].Up();
} else {
ret = max(ret, segs[TreeIdxB].rmq(0, TreeDepthB + 1));
tie(TreeIdxB, TreeDepthB) = Centroids[TreeIdxB].Up();
}
}
if(TreeDepthA > TreeDepthB) swap(TreeDepthA, TreeDepthB);
return (max(ret, segs[TreeIdxA].rmq(TreeDepthA + 1, TreeDepthB + 1)));
}
int main()
{
int N, M;
cin >> N >> M;
vector< edge > edges(M);
for(auto &e : edges) cin >> e.u >> e.v >> e.cost;
sort(begin(edges), end(edges));
int64 cost = 0LL;
UnionFind tree(N);
CentroidPathDecomposition cpd(N);
map< pair< int, int >, int > vs;
for(auto &e : edges) {
e.u--, e.v--;
if(tree.find(e.u) == tree.find(e.v)) continue;
cost += e.cost;
tree.unite(e.u, e.v);
cpd.AddEdge(e.u, e.v);
vs[{e.u, e.v}] = e.cost;
}
cpd.Build();
for(int i = 0; i < cpd.size(); i++) {
segs.push_back(SegmentTree(cpd[i].size()));
}
for(auto &v : vs) {
auto a = cpd.Information(v.first.first);
auto b = cpd.Information(v.first.second);
if(a.first > b.first || (a.first == b.first) && a.second > b.second) swap(a, b);
segs[b.first].update(b.second, v.second);
}
int Q;
cin >> Q;
while(Q--) {
int s, t;
cin >> s >> t;
cout << cost - cpd.getPathMax(--s, --t) << endl;
}
}
Submission Info
Submission Time |
|
Task |
A - Graph |
User |
ei13333 |
Language |
C++14 (GCC 5.4.1) |
Score |
700 |
Code Size |
6519 Byte |
Status |
AC |
Exec Time |
635 ms |
Memory |
6912 KB |
Judge Result
Set Name |
Sample |
subtask1 |
subtask2 |
All |
Score / Max Score |
0 / 0 |
200 / 200 |
300 / 300 |
200 / 200 |
Status |
|
|
|
|
Set Name |
Test Cases |
Sample |
sample_1.txt, sample_2.txt |
subtask1 |
sample_2.txt, subtask_1_1.txt, subtask_1_10.txt, subtask_1_11.txt, subtask_1_2.txt, subtask_1_3.txt, subtask_1_4.txt, subtask_1_5.txt, subtask_1_6.txt, subtask_1_7.txt, subtask_1_8.txt, subtask_1_9.txt |
subtask2 |
sample_1.txt, sample_2.txt, subtask_1_1.txt, subtask_1_10.txt, subtask_1_11.txt, subtask_1_2.txt, subtask_1_3.txt, subtask_1_4.txt, subtask_1_5.txt, subtask_1_6.txt, subtask_1_7.txt, subtask_1_8.txt, subtask_1_9.txt, subtask_2_1.txt, subtask_2_2.txt, subtask_2_3.txt, subtask_2_4.txt, subtask_2_5.txt, subtask_2_6.txt, subtask_2_7.txt, subtask_2_8.txt |
All |
sample_1.txt, sample_2.txt, sample_1.txt, sample_2.txt, subtask_1_1.txt, subtask_1_10.txt, subtask_1_11.txt, subtask_1_2.txt, subtask_1_3.txt, subtask_1_4.txt, subtask_1_5.txt, subtask_1_6.txt, subtask_1_7.txt, subtask_1_8.txt, subtask_1_9.txt, subtask_2_1.txt, subtask_2_2.txt, subtask_2_3.txt, subtask_2_4.txt, subtask_2_5.txt, subtask_2_6.txt, subtask_2_7.txt, subtask_2_8.txt, subtask_3_1.txt, subtask_3_2.txt, subtask_3_3.txt, subtask_3_4.txt, subtask_3_5.txt, subtask_3_6.txt, subtask_3_7.txt, subtask_3_8.txt |
Case Name |
Status |
Exec Time |
Memory |
sample_1.txt |
AC |
1 ms |
256 KB |
sample_2.txt |
AC |
1 ms |
256 KB |
subtask_1_1.txt |
AC |
2 ms |
256 KB |
subtask_1_10.txt |
AC |
195 ms |
3456 KB |
subtask_1_11.txt |
AC |
1 ms |
256 KB |
subtask_1_2.txt |
AC |
42 ms |
1536 KB |
subtask_1_3.txt |
AC |
388 ms |
5760 KB |
subtask_1_4.txt |
AC |
8 ms |
1152 KB |
subtask_1_5.txt |
AC |
9 ms |
1152 KB |
subtask_1_6.txt |
AC |
104 ms |
2176 KB |
subtask_1_7.txt |
AC |
389 ms |
5760 KB |
subtask_1_8.txt |
AC |
8 ms |
1152 KB |
subtask_1_9.txt |
AC |
13 ms |
1152 KB |
subtask_2_1.txt |
AC |
393 ms |
5760 KB |
subtask_2_2.txt |
AC |
393 ms |
5760 KB |
subtask_2_3.txt |
AC |
398 ms |
5760 KB |
subtask_2_4.txt |
AC |
396 ms |
5760 KB |
subtask_2_5.txt |
AC |
15 ms |
1152 KB |
subtask_2_6.txt |
AC |
30 ms |
1280 KB |
subtask_2_7.txt |
AC |
106 ms |
2304 KB |
subtask_2_8.txt |
AC |
393 ms |
5760 KB |
subtask_3_1.txt |
AC |
634 ms |
6912 KB |
subtask_3_2.txt |
AC |
635 ms |
6912 KB |
subtask_3_3.txt |
AC |
243 ms |
2432 KB |
subtask_3_4.txt |
AC |
261 ms |
2432 KB |
subtask_3_5.txt |
AC |
438 ms |
4608 KB |
subtask_3_6.txt |
AC |
536 ms |
5760 KB |
subtask_3_7.txt |
AC |
626 ms |
6912 KB |
subtask_3_8.txt |
AC |
631 ms |
6912 KB |