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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 |
---|---|---|---|---|---|---|---|---|---|
#454869 | #6546. Greedy Bipartite Matching | pandapythoner | TL | 76ms | 20080kb | C++20 | 3.2kb | 2024-06-25 15:55:55 | 2024-06-25 15:55:55 |
Judging History
answer
#pragma GCC optimize("Ofast,unroll-loops")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define flt double
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define rep(i, n) for(int i = 0; i < n; i += 1)
const ll inf = 1e18;
mt19937 rnd(234);
int n, q;
vector<vector<int>> g;
vector<vector<pair<int, int>>> edges;
vector<int> result;
vector<int> is_good_left, is_good_right, good_left;
int usdc;
vector<int> usd;
vector<int> p;
vector<int> usd_left;
bool dfs(int v) {
usd[v] = usdc;
for (auto to : g[v]) {
if (p[to] == -1) {
p[to] = v;
usd_left[v] = true;
return true;
}
if (usd[p[to]] == usdc) {
continue;
}
if (dfs(p[to])) {
p[to] = v;
usd_left[v] = true;
return true;
}
}
return false;
}
void solve() {
is_good_left.assign(n, true);
is_good_right.assign(n, true);
good_left.resize(n);
rep(i, n) good_left[i] = i;
usd.assign(n, 0);
usdc = 1;
g.assign(n, vector<int>());
result.resize(q);
p.assign(n, -1);
int cur_matching = 0;
usd_left.assign(n, false);
rep(eid, q) {
for (auto [u, v] : edges[eid]) {
if (is_good_left[u] and is_good_right[v]) {
g[u].push_back(v);
}
}
++usdc;
for (auto v : good_left) {
if (usd_left[v]) {
continue;
}
if (dfs(v)) {
cur_matching += 1;
++usdc;
}
}
result[eid] = cur_matching;
if (eid + 1 == q) {
break;
}
++usdc;
queue<int> q;
for (auto v : good_left) {
if (usd_left[v]) {
continue;
}
q.push(v);
usd[v] = usdc;
}
while (!q.empty()) {
int v = q.front();
q.pop();
for (auto to : g[v]) {
assert(p[to] != -1);
is_good_right[to] = false;
if (usd[p[to]] == usdc) {
continue;
}
usd[p[to]] = usdc;
q.push(p[to]);
}
}
vector<int> new_good_left;
for (auto v : good_left) {
if (usd[v] == usdc) {
new_good_left.push_back(v);
} else {
is_good_left[v] = false;
}
}
good_left.swap(new_good_left);
}
}
int32_t main() {
if (1) {
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
cin >> n >> q;
edges.assign(q, vector<pair<int, int>>());
rep(i, q) {
int t;
cin >> t;
edges[i].resize(t);
rep(j, t) {
int u, v;
cin >> u >> v;
--u;
--v;
edges[i][j] = make_pair(u, v);
}
}
solve();
for (int i = 0; i < q; i += 1) {
cout << result[i] << " ";
}
cout << "\n";
return 0;
}
/*
3 4
2
1 1
1 2
2
1 1
2 2
2
1 3
3 2
1
3 3
*/
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 3556kb
input:
3 4 2 1 1 1 2 2 1 1 2 2 2 1 3 3 2 1 3 3
output:
1 2 2 3
result:
ok 4 number(s): "1 2 2 3"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3544kb
input:
0 0
output:
result:
ok 0 number(s): ""
Test #3:
score: 0
Accepted
time: 0ms
memory: 3568kb
input:
2 2 0 2 1 2 1 2
output:
0 1
result:
ok 2 number(s): "0 1"
Test #4:
score: 0
Accepted
time: 76ms
memory: 20080kb
input:
100000 1 200000 78475 45796 32145 46393 92550 13904 73461 34145 96461 92851 56319 77067 77530 84437 76343 51543 77507 99269 76411 89382 1779 61393 43608 96136 84269 74828 14858 35967 32085 94909 19877 175 1482 94391 12424 55020 64369 92588 81296 7903 25433 46033 36294 61129 73556 84837 8419 10215 12...
output:
100000
result:
ok 1 number(s): "100000"
Test #5:
score: 0
Accepted
time: 67ms
memory: 15464kb
input:
100000 1 200000 56816 52517 2577 76202 40378 1758 50464 66497 15834 50880 9829 16331 80693 9963 51096 17591 15871 35192 91302 65510 90775 57493 11891 8967 44787 41896 3387 35479 93471 47453 84804 93636 90746 34877 18202 38718 7473 34258 36581 19533 13249 27525 6442 69870 8822 61871 94537 67714 41396...
output:
100000
result:
ok 1 number(s): "100000"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3636kb
input:
4 1 7 2 2 3 3 1 1 4 2 2 3 3 1 4 3
output:
3
result:
ok 1 number(s): "3"
Test #7:
score: -100
Time Limit Exceeded
input:
100000 1 199999 25371 25371 85965 85964 416 416 16797 16797 12438 12438 45410 45409 63006 63005 22156 22156 87829 87828 84014 84014 37308 37308 72325 72325 83704 83704 55391 55390 6781 6780 78091 78091 9376 9376 82193 82193 74695 74695 49842 49842 15799 15799 69856 69855 82949 82948 97390 97389 205 ...