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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 |
---|---|---|---|---|---|---|---|---|---|
#578579 | #5704. Joker | isirazeev | 0 | 62ms | 29600kb | C++20 | 4.0kb | 2024-09-20 20:08:15 | 2024-09-20 20:08:15 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
#define int long long
struct change {
int *cell, val, time;
};
struct DSU {
vector<int> p, sz, len;
vector<change> changes;
int flag, timer;
void init(int n) {
p.resize(n), sz.resize(n), len.resize(n);
for (int i = 0; i < n; i++)
p[i] = i, sz[i] = 1, len[i] = 0;
flag = -1, timer = 0;
}
void undo() {
if (changes.empty()) return;
int time = changes.back().time;
if (time == flag) flag = -1;
while (!changes.empty() &&
changes.back().time == time) {
*changes.back().cell = changes.back().val;
changes.pop_back();
}
}
pair<int, int> find(int v) {
if (v == p[v]) return {v, 0};
auto pr = find(p[v]);
return {pr.first, (pr.second + len[v]) % 2};
}
bool isBipartite() {
return flag == -1;
}
void unite(int u, int v) {
timer++;
auto P = find(u), Q = find(v);
int p1 = P.first, p2 = Q.first;
if (sz[p1] > sz[p2]) swap(p1, p2), swap(P, Q);
if (p1 == p2) {
if (P.second == Q.second && flag == -1) flag = timer;
changes.emplace_back(&p[p1], p1, timer);
return;
}
changes.emplace_back(&p[p1], p[p1], timer);
p[p1] = p2;
changes.emplace_back(&len[p1], len[p1], timer);
len[p1] = (P.second + Q.second + 1) % 2;
changes.emplace_back(&sz[p2], sz[p2], timer);
sz[p2] += sz[p1];
}
};
struct update {
char type;
int u, v;
};
struct QueueUndoTrick {
DSU T;
int bottom = 0;
vector<update> updates;
void init(int n) {
T.init(n);
}
void advance_bottom() {
while (bottom < updates.size() && updates[bottom].type == 'B') bottom++;
}
void reverse_updates() {
for (int i = 0; i < (int) updates.size(); i++)
T.undo();
reverse(updates.begin(), updates.end());
for (int i = 0; i < (int) updates.size(); i++) {
T.unite(updates[i].u, updates[i].v);
updates[i].type = 'A';
}
bottom = 0;
}
void fix() {
if (updates.empty() || updates.back().type == 'A') return;
advance_bottom();
vector<update> saveA, saveB = {updates.back()};
updates.pop_back();
while (saveA.size() != saveB.size() && updates.size() > bottom) {
if (updates.back().type == 'A')
saveA.emplace_back(updates.back());
else
saveB.emplace_back(updates.back());
T.undo();
updates.pop_back();
}
reverse(saveA.begin(), saveA.end());
reverse(saveB.begin(), saveB.end());
for (auto &u: saveB)
updates.emplace_back(u), T.unite(u.u, u.v);
for (auto &u: saveA)
updates.emplace_back(u), T.unite(u.u, u.v);
advance_bottom();
}
void undo() {
advance_bottom();
if (bottom == updates.size())
reverse_updates();
fix();
T.undo();
updates.pop_back();
}
void unite(int u, int v) {
T.unite(u, v);
updates.emplace_back('B', u, v);
}
bool isBipartite() {
return T.isBipartite();
}
};
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr), cout.tie(nullptr);
int n, m, q;
cin >> n >> m >> q;
QueueUndoTrick T;
vector<pair<int, int>> e(m);
for (int i = 0; i < m; i++) cin >> e[i].first >> e[i].second;
T.init(n);
int r = -1, right[m];
for (int i = 0; i < m; i++) {
while (r < m && T.isBipartite()) {
r++;
if (r < m)
T.unite(e[r].first, e[r].second);
}
right[i] = r;
T.undo();
}
for (int i = 0; i < q; i++) {
int L, R;
cin >> L >> R;
if (right[L - 1] <= R - 1)
cout << "NO\n";
else
cout << "YES\n";
}
return 0;
}
詳細信息
Subtask #1:
score: 0
Wrong Answer
Test #1:
score: 6
Accepted
time: 0ms
memory: 3616kb
input:
6 8 2 1 3 1 5 1 6 2 5 2 6 3 4 3 5 5 6 4 8 4 7
output:
NO YES
result:
ok 2 lines
Test #2:
score: 0
Wrong Answer
time: 0ms
memory: 3612kb
input:
2 1 1 1 2 1 1
output:
YES
result:
wrong answer 1st lines differ - expected: 'NO', found: 'YES'
Subtask #2:
score: 0
Skipped
Dependency #1:
0%
Subtask #3:
score: 0
Wrong Answer
Test #55:
score: 0
Wrong Answer
time: 62ms
memory: 29600kb
input:
100000 199997 200000 79109 44896 79109 66117 66117 91800 91800 24387 24387 74514 48558 74514 48558 37561 37561 76920 79598 76920 79598 69196 69196 79004 49065 79004 70038 49065 15497 70038 15497 67507 25073 67507 25073 41762 41762 71848 71848 32073 32073 43754 72852 43754 41209 72852 68112 41209 629...
output:
NO NO YES YES NO NO NO NO YES NO NO YES NO YES NO YES NO NO NO NO NO YES NO NO NO YES NO NO NO NO NO NO NO NO NO NO NO YES NO NO NO NO YES NO NO NO NO NO NO NO YES NO NO NO NO NO NO NO NO NO NO NO YES NO NO YES NO NO YES NO NO NO YES NO NO NO NO NO NO NO NO YES NO NO NO NO NO NO NO YES NO NO NO NO Y...
result:
wrong answer 4th lines differ - expected: 'NO', found: 'YES'
Subtask #4:
score: 0
Skipped
Dependency #3:
0%
Subtask #5:
score: 0
Skipped
Dependency #2:
0%
Subtask #6:
score: 0
Skipped
Dependency #1:
0%