QOJ.ac
QOJ
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 |
---|---|---|---|---|---|---|---|---|---|
#190520 | #6735. Tree | ucup-team004 | RE | 0ms | 3688kb | C++20 | 5.5kb | 2023-09-29 01:59:21 | 2023-09-29 01:59:21 |
Judging History
answer
#include <bits/stdc++.h>
using i64 = long long;
constexpr i64 inf = 1E18;
struct Info {
i64 ans = 0;
i64 len = -inf;
i64 vl = -inf;
i64 vr = -inf;
};
constexpr int N = 1 << 18;
Info info[N];
Info operator+(const Info &a, const Info &b) {
Info c;
c.ans = std::max({a.ans, b.ans, a.vr + b.vl});
c.len = std::max(-inf, a.len + b.len);
c.vl = std::max(a.vl, a.len + b.vl);
c.vr = std::max(b.vr, a.vr + b.len);
return c;
}
Info query(int p, int l, int r, int x, int y) {
if (l >= y || r <= x) {
return {};
}
if (l >= x && r <= y) {
return info[p];
}
int m = (l + r) / 2;
return query(2 * p, l, m, x, y) + query(2 * p + 1, m, r, x, y);
}
void pull(int p) {
info[p] = info[2 * p] + info[2 * p + 1];
}
void modify(int p, int l, int r, int x, const Info &v) {
if (r - l == 1) {
info[p] = v;
return;
}
int m = (l + r) / 2;
if (x < m) {
modify(2 * p, l, m, x, v);
} else {
modify(2 * p + 1, m, r, x, v);
}
pull(p);
}
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
int n, q;
std::cin >> n >> q;
std::vector<int> a(n);
for (int i = 0; i < n; i++) {
std::cin >> a[i];
}
std::vector<int> p(n);
p[0] = -1;
for (int i = 1; i < n; i++) {
std::cin >> p[i];
p[i]--;
}
std::vector<int> c(n);
for (int i = 1; i < n; i++) {
std::cin >> c[i];
}
std::vector<int> w(n);
for (int i = 1; i < n; i++) {
std::cin >> w[i];
}
std::vector<int> dep(n), siz(n), in(n), top(n), bot(n);
std::vector<std::vector<int>> adj(n);
for (int i = 1; i < n; i++) {
adj[p[i]].push_back(i);
}
auto dfs1 = [&](auto self, int x) -> void {
siz[x] = 1;
for (auto &y : adj[x]) {
dep[y] = dep[x] + 1;
self(self, y);
siz[x] += siz[y];
if (siz[y] > siz[adj[x][0]]) {
std::swap(y, adj[x][0]);
}
}
};
dfs1(dfs1, 0);
std::vector<std::multiset<std::pair<std::pair<int, int>, i64>>> chain(n);
std::vector<std::multiset<std::pair<int, i64>>> val(n);
std::vector<i64> sub(n);
auto get = [&](int x = 0) {
return query(1, 0, n, in[x], in[bot[x]] + 1);
};
auto getmax = [&](const auto &s, const auto &v, int cnt = 1) {
i64 ans = 0;
auto it = s.upper_bound({v, inf});
while (cnt-- && it != s.begin()) {
it--;
if (it->first == v) {
ans += it->second;
}
}
return ans;
};
auto add = [&](int x, int a, int c, i64 v) {
val[x].extract({a, getmax(chain[x], std::make_pair(a, c), 2)});
chain[x].emplace(std::make_pair(a, c), v);
val[x].emplace(a, getmax(chain[x], std::make_pair(a, c), 2));
};
auto del = [&](int x, int a, int c, i64 v) {
val[x].extract({a, getmax(chain[x], std::make_pair(a, c), 2)});
chain[x].extract({std::make_pair(a, c), v});
val[x].emplace(a, getmax(chain[x], std::make_pair(a, c), 2));
};
auto insert = [&](int x) {
if (!x) {
return;
}
int y = p[x];
auto res = get(x);
add(y, a[x], c[x], std::max(0LL, res.vl) + w[x]);
val[y].emplace(-1, res.ans);
};
auto erase = [&](int x) {
if (!x) {
return;
}
int y = p[x];
auto res = get(x);
del(y, a[x], c[x], std::max(0LL, res.vl) + w[x]);
val[y].extract({-1, res.ans});
};
auto update = [&](int x) {
Info v;
sub[x] = std::max(getmax(val[x], a[x]), getmax(val[x], -1));
if (!adj[x].empty()) {
int y = adj[x][0];
if (a[x] == a[y]) {
v.vr = getmax(chain[x], std::make_pair(a[y], c[y]));
}
if (a[y] == a[x] && c[y] == c[x]) {
v.len = w[x];
}
}
if (top[x] != x) {
int y = p[x];
if (a[y] == a[x]) {
v.vl = w[x] + getmax(chain[x], std::make_pair(a[x], c[x]));
}
}
v.ans = std::max({sub[x], v.vl, v.vr});
modify(1, 0, n, in[x], v);
};
int cur = 0;
auto dfs2 = [&](auto self, int x) -> void {
in[x] = cur++;
for (auto y : adj[x]) {
top[y] = y == adj[x][0] ? top[x] : y;
self(self, y);
if (y != adj[x][0]) {
insert(y);
}
}
bot[x] = adj[x].empty() ? x : bot[adj[x][0]];
update(x);
};
dfs2(dfs2, 0);
auto change = [&](int x, int y) {
for (int i = x; i != -1; i = p[top[i]]) {
erase(top[i]);
}
a[x] = y;
if (top[x] != x) {
update(p[x]);
}
if (!adj[x].empty()) {
update(adj[x][0]);
}
for (int i = x; i != -1; i = p[top[i]]) {
update(i);
insert(top[i]);
}
};
auto answer = [&]() {
auto res = get();
std::cout << std::max(res.vl, res.ans) << "\n";
};
answer();
while (q--) {
int x, y;
std::cin >> x >> y;
x--;
change(x, y);
answer();
}
return 0;
}
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3660kb
input:
5 5 5 4 3 4 5 1 2 3 1 2 2 2 2 4 9 2 6 2 5 4 5 5 4 3 5 2 1
output:
6 10 10 4 15 2
result:
ok 6 numbers
Test #2:
score: 0
Accepted
time: 0ms
memory: 3688kb
input:
13 21 1 2 1 2 4 4 2 1 4 2 3 6 1 1 1 2 3 2 6 7 8 9 10 8 8 2 13 1 1 1 2 2 1 2 1 2 1 472868230 94771637 209247951 483753517 822923242 938504499 413445582 328056598 487969741 355938152 902390974 28610378 2 4 7 4 10 1 8 4 2 3 5 2 11 4 9 3 6 2 6 1 4 1 6 1 2 3 8 2 5 2 6 2 8 4 8 2 1 4 11 4 12 2
output:
209247951 822923242 938504499 938504499 1351950081 1351950081 1351950081 1351950081 1351950081 413445582 413445582 413445582 413445582 413445582 94771637 94771637 94771637 413445582 94771637 0 0 902390974
result:
ok 22 numbers
Test #3:
score: -100
Runtime Error
input:
200000 199999 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1064 1...