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ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#182959 | #6737. Neighbourhood | ucup-team004# | WA | 5951ms | 199636kb | C++20 | 5.8kb | 2023-09-18 19:39:02 | 2023-09-18 19:39:02 |
Judging History
answer
#include <bits/stdc++.h>
using i64 = long long;
constexpr int N = 2E5;
constexpr int LogN = 20;
int n, q;
int x[N], y[N], w[N];
std::vector<int> adj[N];
int cdep[N], cpar[N], siz[N];
int par[LogN][N], in[LogN][N], out[LogN][N], seq[LogN][N];
int st[LogN][N];
i64 A[LogN][N], B[LogN][N], tag[LogN][N];
bool vis[N];
int cur[LogN];
int blk[N + 1];
void dfs(int d, int x) {
in[d][x] = cur[d]++;
seq[d][in[d][x]] = x;
siz[x] = 1;
for (auto y : adj[x]) {
if (vis[y] || y == par[d][x]) {
continue;
}
par[d][y] = x;
dfs(d, y);
siz[x] += siz[y];
}
out[d][x] = cur[d];
}
int find(int x, int p, int s) {
for (auto y : adj[x]) {
if (vis[y] || y == p || 2 * siz[y] <= s) {
continue;
}
return find(y, x, s);
}
return x;
}
int solve(int d, int r) {
int t = cur[d];
par[d][r] = -1;
dfs(d, r);
r = find(r, -1, siz[r]);
par[d][r] = -1;
cur[d] = t;
dfs(d, r);
cdep[r] = d;
vis[r] = true;
for (auto y : adj[r]) {
if (vis[y]) {
continue;
}
y = solve(d + 1, y);
cpar[y] = r;
}
return r;
}
int lca(int u, int v) {
if (u == v) {
return u;
}
u = in[0][u];
v = in[0][v];
if (u > v) {
std::swap(u, v);
}
int k = std::__lg(v - u);
int a = st[k][u];
int b = st[k][v - (1 << k)];
return in[0][a] < in[0][b] ? a : b;
}
i64 getdep(int u) {
int x = in[0][u];
return A[0][x] + tag[0][x - x % blk[n]];
}
i64 dist(int u, int v) {
int l = lca(u, v);
return getdep(u) + getdep(v) - 2 * getdep(l);
}
void add(int d, int x, int l, int r, int c) {
int L = in[d][x], R = out[d][x];
int n = R - L;
int b = blk[n];
int lb = (l - L) / b;
int rb = (r - 1 - L) / b;
if (lb == rb) {
for (int i = l; i < r; i++) {
A[d][i] += c;
}
l = L + lb * b;
r = std::min(R, l + b);
std::copy(A[d] + l, A[d] + r, B[d] + l);
std::sort(B[d] + l, B[d] + r);
} else {
for (int i = l; i < L + (lb + 1) * b; i++) {
A[d][i] += c;
}
for (int i = lb + 1; i < rb; i++) {
tag[d][L + i * b] += c;
}
for (int i = L + rb * b; i < r; i++) {
A[d][i] += c;
}
l = L + lb * b;
r = std::min(R, l + b);
std::copy(A[d] + l, A[d] + r, B[d] + l);
std::sort(B[d] + l, B[d] + r);
l = L + rb * b;
r = std::min(R, l + b);
std::copy(A[d] + l, A[d] + r, B[d] + l);
std::sort(B[d] + l, B[d] + r);
}
}
int get(int d, int x, int l, int r, i64 v) {
if (l == r) {
return 0;
}
int L = in[d][x], R = out[d][x];
int n = R - L;
int b = blk[n];
int lb = (l - L) / b;
int rb = (r - 1 - L) / b;
int res = 0;
if (lb == rb) {
i64 t = tag[d][L + lb * b];
for (int i = l; i < r; i++) {
res += (A[d][i] + t <= v);
}
} else {
i64 t = tag[d][L + lb * b];
for (int i = l; i < L + (lb + 1) * b; i++) {
res += (A[d][i] + t <= v);
}
for (int i = lb + 1; i < rb; i++) {
int l = L + i * b;
int r = l + b;
t = tag[d][l];
res += std::upper_bound(B[d] + l, B[d] + r, v - t) - B[d] - l;
}
t = tag[d][L + rb * b];
for (int i = L + rb * b; i < r; i++) {
res += (A[d][i] + t <= v);
}
}
return res;
}
void modify(int i, int c) {
int X = x[i], Y = y[i];
int u = X, v = Y;
while (cdep[u] > cdep[v]) {
u = cpar[u];
}
while (cdep[v] > cdep[u]) {
v = cpar[v];
}
while (u != v) {
u = cpar[u];
v = cpar[v];
}
while (u != -1) {
int d = cdep[u];
int l = std::max(in[d][X], in[d][Y]);
int r = std::min(out[d][X], out[d][Y]);
add(d, u, l, r, c);
u = cpar[u];
}
}
int query(int x, i64 L) {
int ans = 0;
int y = -1;
for (int i = x; i != -1; y = i, i = cpar[i]) {
i64 dis = dist(x, i);
int d = cdep[i];
if (y != -1) {
ans += get(d, i, in[d][i], in[d][y], L - dis);
ans += get(d, i, out[d][y], out[d][i], L - dis);
} else {
ans += get(d, i, in[d][i], out[d][i], L - dis);
}
}
return ans;
}
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
for (int i = 1; i <= N; i++) {
blk[i] = std::sqrt(i);
}
std::cin >> n >> q;
for (int i = 1; i < n; i++) {
std::cin >> x[i] >> y[i] >> w[i];
x[i]--, y[i]--;
adj[x[i]].push_back(y[i]);
adj[y[i]].push_back(x[i]);
}
cpar[solve(0, 0)] = -1;
for (int i = 0; i < n; i++) {
if (in[0][i] != 0) {
st[0][in[0][i] - 1] = par[0][i];
}
}
for (int k = 0; k + 1 < LogN; k++) {
for (int i = 0; i + (2 << k) <= n - 1; i++) {
int a = st[k][i];
int b = st[k][i + (1 << k)];
st[k + 1][i] = in[0][a] < in[0][b] ? a : b;
}
}
for (int i = 1; i < n; i++) {
modify(i, w[i]);
}
for (int _ = 0; _ < q; _++) {
int o;
std::cin >> o;
if (o == 1) {
int i, c;
std::cin >> i >> c;
modify(i, c - w[i]);
w[i] = c;
} else {
int x;
i64 d;
std::cin >> x >> d;
x--;
std::cout << query(x, d) << "\n";
}
}
return 0;
}
Details
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Test #1:
score: 100
Accepted
time: 0ms
memory: 32488kb
input:
3 7 1 2 3 2 3 1 2 2 1 2 1 3 2 3 4 1 1 1 2 2 1 2 1 0 2 3 1
output:
2 2 3 3 1 2
result:
ok 6 numbers
Test #2:
score: -100
Wrong Answer
time: 5951ms
memory: 199636kb
input:
200000 200000 1 2 146181238 2 3 45037818 3 4 176924060 4 5 969365276 5 6 683948619 6 7 356268194 7 8 871634797 8 9 630254480 9 10 283061123 10 11 204904965 11 12 838381393 12 13 516373812 13 14 253862710 14 15 223572474 15 16 114452997 16 17 145251056 17 18 905638436 18 19 375445402 19 20 549829545 ...
output:
366 99349 2324 8635 107281 1153 19129 190278 8342 9341 4566 3814 29805 14084 36208 4877 178706 124397 259738 24200 32095 34336 14371 451 5924 5328 10844 57956 8537 251589 22736 153 1447 182 103963 1509 17583 2903 52322 1599 8076 17001 36208 359 61943 3910 23430 3562 66996 136632 130821 7386 123939 2...
result:
wrong answer 1st numbers differ - expected: '219', found: '366'