#include <bits/stdc++.h>
using namespace std;
using db = long double;
using ll = long long;
using pl = pair<ll, ll>;
using pi = pair<int, int>;
#define vt vector
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(), x.end()
#define size(x) ((int) (x).size())
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define ROF(i, a, b) for (int i = (b) - 1; i >= (a); i--)
#define F0R(i, b) FOR (i, 0, b)
#define endl '\n'
const ll INF = 1e18;
const int inf = 1e9;
template<typename Tuple, size_t... Is>
void print_tuple(const Tuple& t, index_sequence<Is...>) {
((cerr << (Is == 0 ? "{" : ", ") << get<Is>(t)), ...);
cerr << "}";
}
template<typename... Args>
ostream& operator<<(ostream& os, const tuple<Args...>& t) {
print_tuple(t, index_sequence_for<Args...>{});
return os;
}
ostream& operator<<(ostream& os, string& s) {
for (char c : s) os << c;
return os;
}
template<template<typename> class Container, typename T>
ostream& operator<<(ostream& os, Container<T> o) {
os << "{";
int g = size(o);
for (auto i : o) os << i << ((--g) == 0 ? "" : ", ");
os << "}";
return os;
}
template<typename T, typename V>
ostream& operator<<(ostream& os, const pair<T, V> p) {
os << "{" << p.f << ", " << p.s << "}";
return os;
}
template <typename T, typename... V>
void printer(const char *names, T &&head, V &&...tail) {
int i = 0;
while (names[i] != '\0' && names[i] != ',') i++;
constexpr bool is_str = is_same_v<decay_t<T>, const char*>;
if constexpr (is_str) cerr << head; // ignore directly passed strings
else cerr.write(names, i) << " = " << head;
if constexpr (sizeof...(tail)) cerr << (is_str ? "" : ","), printer(names + i + 1, tail...);
else cerr << endl;
}
#ifdef LOCAL
#define dbg(...) std::cerr << __LINE__ << ": ", printer(#__VA_ARGS__, __VA_ARGS__)
#else
#define dbg(x...)
#define cerr if (0) std::cerr
#endif
/*
range perfect matching goes crazy
since kuhn's is more efficient when lhs is small, we need the girls to be on the left
we want to find the maximum r for each l, and two pointer it
*/
int n, m, k; // n is lhs (girls), m is rhs (boys)
vt<unordered_set<int>> adj; // l -> r
vt<int> mate; // mate = rhs -> lhs
vt<bool> seen;
bool dfs(int u) {
if (seen[u]) return false;
seen[u] = true;
for (int v : adj[u]) {
if (mate[v] == -1 || dfs(mate[v])) {
mate[v] = u;
return true;
}
}
return false;
}
main() {
cin.tie(0)->sync_with_stdio(0);
cin >> m >> n >> k;
adj.resize(n);
mate.resize(m, -1);
vt<vt<int>> radj(m);
F0R (i, k) {
int u, v; cin >> u >> v; u--, v--;
// u is boy, v is girl
radj[u].pb(v);
}
// enqueue all the unmatched girls
queue<int> to_match;
F0R (i, n) to_match.push(i);
// attempt to augment from u on lhs
auto augment = [&] (int u) {
seen.assign(n, 0);
return dfs(u);
};
ll ans = 0;
int r = -1;
F0R (l, m) {
while (size(to_match)) {
// try augment
while (size(to_match) && augment(to_match.front())) {
to_match.pop();
}
if (!size(to_match)) break;
// still bad
if (r == m - 1) {
cout << ans << endl;
return 0;
}
r++;
// add these edges
for (int u : radj[r]) assert(adj[u].insert(r).s);
}
// add # of possible right endpoints for l
dbg(l, r);
ans += m - r;
assert(r - l + 1 >= n);
// remove edges
for (int u : radj[l]) assert(adj[u].erase(l));
// check if we unmatched someone by removing l
if (mate[l] != -1) {
to_match.push(mate[l]);
mate[l] = -1;
}
}
cout << ans << endl;
}
Compilation message
marriage.cpp:98:5: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
98 | main() {
| ^~~~
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
0 ms |
348 KB |
Output is correct |
| 2 |
Correct |
0 ms |
348 KB |
Output is correct |
| 3 |
Correct |
1 ms |
348 KB |
Output is correct |
| 4 |
Correct |
0 ms |
348 KB |
Output is correct |
| 5 |
Correct |
1 ms |
348 KB |
Output is correct |
| 6 |
Correct |
0 ms |
348 KB |
Output is correct |
| 7 |
Correct |
0 ms |
348 KB |
Output is correct |
| 8 |
Correct |
0 ms |
348 KB |
Output is correct |
| 9 |
Correct |
0 ms |
348 KB |
Output is correct |
| 10 |
Correct |
0 ms |
344 KB |
Output is correct |
| 11 |
Correct |
1 ms |
344 KB |
Output is correct |
| 12 |
Correct |
0 ms |
348 KB |
Output is correct |
| 13 |
Correct |
0 ms |
348 KB |
Output is correct |
| 14 |
Correct |
0 ms |
344 KB |
Output is correct |
| 15 |
Correct |
0 ms |
348 KB |
Output is correct |
| 16 |
Correct |
0 ms |
348 KB |
Output is correct |
| 17 |
Correct |
1 ms |
348 KB |
Output is correct |
| 18 |
Correct |
0 ms |
348 KB |
Output is correct |
| 19 |
Correct |
1 ms |
348 KB |
Output is correct |
| 20 |
Correct |
1 ms |
348 KB |
Output is correct |
| 21 |
Correct |
0 ms |
348 KB |
Output is correct |
| 22 |
Correct |
0 ms |
348 KB |
Output is correct |
| 23 |
Correct |
0 ms |
348 KB |
Output is correct |
| 24 |
Correct |
0 ms |
348 KB |
Output is correct |
| 25 |
Correct |
7 ms |
708 KB |
Output is correct |
| 26 |
Correct |
1 ms |
344 KB |
Output is correct |
| 27 |
Correct |
0 ms |
348 KB |
Output is correct |
| 28 |
Correct |
1 ms |
348 KB |
Output is correct |
| 29 |
Correct |
2 ms |
856 KB |
Output is correct |
| 30 |
Correct |
1 ms |
860 KB |
Output is correct |
| 31 |
Correct |
222 ms |
1876 KB |
Output is correct |
| 32 |
Correct |
2 ms |
600 KB |
Output is correct |
| 33 |
Correct |
1 ms |
344 KB |
Output is correct |
| 34 |
Correct |
4 ms |
604 KB |
Output is correct |
| 35 |
Correct |
119 ms |
4692 KB |
Output is correct |
| 36 |
Correct |
80 ms |
4424 KB |
Output is correct |
| 37 |
Correct |
534 ms |
1712 KB |
Output is correct |
| 38 |
Correct |
18 ms |
5212 KB |
Output is correct |
| 39 |
Correct |
88 ms |
1256 KB |
Output is correct |
| 40 |
Correct |
3 ms |
1372 KB |
Output is correct |
| 41 |
Correct |
6 ms |
1720 KB |
Output is correct |
| 42 |
Correct |
6 ms |
2652 KB |
Output is correct |
| 43 |
Correct |
17 ms |
3160 KB |
Output is correct |
| 44 |
Correct |
17 ms |
5228 KB |
Output is correct |
| 45 |
Correct |
11 ms |
2652 KB |
Output is correct |
| 46 |
Correct |
29 ms |
3412 KB |
Output is correct |
| 47 |
Correct |
18 ms |
6236 KB |
Output is correct |
| 48 |
Correct |
17 ms |
5836 KB |
Output is correct |
| 49 |
Correct |
38 ms |
3412 KB |
Output is correct |
| 50 |
Correct |
207 ms |
1628 KB |
Output is correct |
