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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#579065 | #5148. Tree Distance | alexz1205 | WA | 348ms | 81220kb | C++14 | 6.0kb | 2024-09-21 07:15:06 | 2024-09-21 07:15:06 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
const int N = 2e5, M = 1<<18, Q = 1e6;
typedef long long int lint;
int n, q;
vector<array<lint, 2>> con[N];
lint dist[N];
lint dep[N];
lint sz[N];
array<lint, 3> queries[Q];
lint ans[Q];
namespace lca{
int binJump[N][20];
bool precomp = 0;
void calcBinJump(){
for (int i = 1; i < 20; i ++){
for (int x = 0; x < n; x ++){
binJump[x][i] = binJump[binJump[x][i-1]][i-1];
}
}
precomp = 1;
}
int lca(int a, int b){
int dif = dep[a] - dep[b];
while (dif > 0){
a = binJump[a][__builtin_ctz(dif)];
dif = dep[a] - dep[b];
}
swap(a, b);
dif = dep[a] - dep[b];
while (dif > 0){
a = binJump[a][__builtin_ctz(dif)];
dif = dep[a] - dep[b];
}
if (a == b){
return a;
}
for (int x = 19; x >= 0; x --){
if (binJump[a][x] != binJump[b][x]){
a = binJump[a][x];
b = binJump[b][x];
}
}
return binJump[a][0];
}
};
namespace precomp{
void dfs(int i, int p){
lca::binJump[i][0] = p;
sz[i] = 1;
for (array<lint, 2> e: con[i]){
if (e[0] == p) continue;
dist[e[0]] = dist[i] + e[1];
dep[e[0]] = dep[i] + 1;
dfs(e[0], i);
sz[i] += sz[e[0]];
}
}
};
namespace decomp{
int r;
vector<lint> con[N];
lint sz[N];
bool cent[N];
void dfs(int i, int p){
sz[i] = 1;
for (array<lint, 2> e: ::con[i]){
if (e[0] == p) continue;
if (cent[e[0]]) continue;
dfs(e[0], i);
sz[i] += sz[e[0]];
}
}
int findCent(int i, int p, int s){
for (array<lint, 2> e: ::con[i]){
if (e[0] == p) continue;
if (cent[e[0]]) continue;
if (sz[e[0]] >= sz[s]){
return findCent(e[0], i, s);
}
}
return i;
}
int buildDecomp(int i){
dfs(i, i);
int r = findCent(i, i, i);
cent[r] = 1;
for (array<lint, 2> e: ::con[i]){
if (cent[e[0]]) continue;
con[i].push_back(buildDecomp(e[0]));
}
return r;
}
void decomp(){
r = buildDecomp(0);
}
};
lint distN(int a, int b){
int c = lca::lca(a, b);
return dist[a] + dist[b] - dist[c] - dist[c];
}
namespace sign{
set<array<int, 2>> nec;
set<array<lint, 3>> events;
set<int> under[N];
int ind = 0;
void sign(int i, int p, set<int> &pSet){
set<int> under;
for (int x: decomp::con[i]){
sign(x, i, under);
}
under.insert(i);
//vector<lint> dists;
/*
cout << i << " POINTS" << endl;
for (int x: under){
cout << x << " ";
}
cout << endl;
*/
//for (int x: under){
//dists.push_back(distN(x, i));
//}
set<pair<lint, int>> ord;
for (int v: under){
int vD = distN(v, i);
while (!ord.empty() && ord.rbegin()->first >= vD){
int j = ord.rbegin()->second;
nec.insert({j, v});
ind ++;
int d = ord.rbegin()->first + vD;
events.insert({j, d, ind});
events.insert({v, d, ind});
ord.erase(--ord.end());
}
//cout << vD << " " << v << endl;
ord.insert({vD, v});
}
ord.clear();
for (auto it = under.rbegin(); it != under.rend(); ++ it){
int v = *it;
int vD = distN(v, i);
while (!ord.empty() && ord.rbegin()->first >= vD){
int j = ord.rbegin()->second;
nec.insert({j, v});
ind ++;
int d = ord.rbegin()->first + vD;
//int d = distN(j, v);
events.insert({j, d, ind});
events.insert({v, d, ind});
ord.erase(--ord.end());
}
//cout << vD << " " << v << endl;
ord.insert({vD, v});
}
if (p != -1){
pSet.insert(under.begin(), under.end());
}
}
void findSign(){
set<int> temp;
sign(decomp::r, -1, temp);
}
};
int B;
void prep(){
scanf("%d", &n);
for (int x = 1; x < n; x ++){
int a, b, c;
scanf("%d %d %d", &a, &b, &c);
a --, b --;
con[a].push_back({b, c});
con[b].push_back({a, c});
}
scanf("%d", &q);
for (int x = 0; x < q; x ++){
int l, r;
scanf("%d %d", &l, &r);
l --, r --;
queries[x][0] = l;
queries[x][1] = r;
queries[x][2] = x;
}
B = n/(int)sqrt(n);
sort(queries, queries + q, [](array<lint, 3> a, array<lint, 3> b){return (array<lint, 2>){a[0]/B, a[1]} < (array<lint, 2>){b[0]/B, b[1]};});
/*
for (int x = 0; x < q; x ++){
cout << queries[x][0] << " " << queries[x][1] << " " << queries[x][2] << endl;
}
*/
dep[0] = dist[0] = 0;
precomp::dfs(0, 0);
lca::calcBinJump();
if (n == 199999){
return;
}
decomp::decomp();
if (n == 199999){
return;
}
sign::findSign();
/*
for (array<int, 2> p : sign::nec){
cout << p[0] << " " << p[1] << endl;
cout << distN(p[0], p[1]) << endl;
}
for (array<lint, 3> p : sign::events){
cout << p[0] << " " << p[1] << " " << p[2] << endl;
}
*/
}
int main(){
prep();
if (n == 199999){
return 0;
}
int l = -1;
int r = -1;
set<array<lint, 2>> rans;
lint val = 1e18;
decltype(sign::events.begin()) at;
for (int x = 0; x < n; x ++){
int k = queries[x][2];
if ((queries[x][0]/B)*B != l){
rans.clear();
val = 1e18;
l = (queries[x][0]/B) * B;
r = l + B;
at = sign::events.lower_bound({r, -1, -1});
}
ans[k] = 1e18;
set<array<lint, 2>> back;
if (queries[x][1] < r){
for (auto it = sign::events.lower_bound({queries[x][0], -1, -1}); (*it)[0] <= queries[x][1]; ++ it){
if (!back.insert({(*it)[2], (*it)[1]}).second){
ans[k] = min(ans[k], (*it)[1]);
continue;
}
}
continue;
}
while ((*at)[0] <= queries[x][1]){
if (!rans.insert({(*at)[2], (*at)[1]}).second){
val = min(val, (*at)[1]);
at ++;
continue;
}
at ++;
}
ans[k] = val;
for (auto it = sign::events.lower_bound({queries[x][0], -1, -1}); (*it)[0] < r; ++ it){
if (rans.find({(*it)[2], (*it)[1]}) != rans.end()){
ans[k] = min(ans[k], (*it)[1]);
continue;
}
if (!back.insert({(*it)[2], (*it)[1]}).second){
ans[k] = min(ans[k], (*it)[1]);
continue;
}
}
}
for (int x = 0; x < q; x ++){
if (ans[x] == 1e18) {
cout << -1 << endl;
continue;
}
cout << ans[x] << endl;
}
}
詳細信息
Test #1:
score: 100
Accepted
time: 3ms
memory: 34784kb
input:
5 1 2 5 1 3 3 1 4 4 3 5 2 5 1 1 1 4 2 4 3 4 2 5
output:
-1 3 7 7 2
result:
ok 5 number(s): "-1 3 7 7 2"
Test #2:
score: -100
Wrong Answer
time: 348ms
memory: 81220kb
input:
199999 31581 23211 322548833 176307 196803 690953895 34430 82902 340232856 36716 77480 466375266 7512 88480 197594480 95680 61864 679567992 19572 14126 599247796 188006 110716 817477802 160165 184035 722372640 23173 188594 490365246 54801 56250 304741654 10103 45884 643490340 127469 154479 214399361...
output:
result:
wrong answer Answer contains longer sequence [length = 999999], but output contains 0 elements