oj.uz

Submission #1027712

# Submission time Handle Problem Language Result Execution time Memory
1027712 2024-07-19T09:25:14 Z caterpillow Marriage questions (IZhO14_marriage) C++17
64 / 100
 219 ms 6992 KB 
#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)) {
            if (r == m - 1) {
                cout << ans << endl;
                return 0;
            }
            r++;

            // add these edges
            for (int u : radj[r]) adj[u].insert(r);

            // try augment
            while (size(to_match) && augment(to_match.front())) {
                to_match.pop();
            }
        }

        // add # of possible right endpoints for l
        ans += m - r;

        // remove edges
        for (int u : radj[l]) adj[u].erase(l);

        // check if we unmatched someone by removing l
        if (mate[l] != -1) {
            to_match.push(mate[l]);
            mate[l] = -1;
        }
    }
}

Compilation message

marriage.cpp:98:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   98 | main() {
      | ^~~~

Subtask #1
64.0 / 100.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 348 KB Output isn't correct
2 Incorrect 0 ms 348 KB Output isn't correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 344 KB Output is correct
5 Correct 0 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 Incorrect 0 ms 348 KB Output isn't correct
9 Correct 1 ms 452 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Incorrect 0 ms 348 KB Output isn't correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 1 ms 348 KB Output is correct
19 Correct 1 ms 348 KB Output is correct
20 Correct 0 ms 348 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 344 KB Output is correct
23 Correct 1 ms 344 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 592 KB Output is correct
26 Incorrect 1 ms 348 KB Output isn't correct
27 Correct 1 ms 344 KB Output is correct
28 Correct 1 ms 452 KB Output is correct
29 Incorrect 2 ms 856 KB Output isn't correct
30 Incorrect 2 ms 856 KB Output isn't correct
31 Correct 59 ms 2220 KB Output is correct
32 Incorrect 2 ms 604 KB Output isn't correct
33 Correct 1 ms 348 KB Output is correct
34 Correct 4 ms 456 KB Output is correct
35 Correct 15 ms 5212 KB Output is correct
36 Correct 12 ms 4848 KB Output is correct
37 Correct 92 ms 2132 KB Output is correct
38 Incorrect 17 ms 5948 KB Output isn't correct
39 Correct 93 ms 1360 KB Output is correct
40 Correct 4 ms 1628 KB Output is correct
41 Incorrect 7 ms 1884 KB Output isn't correct
42 Incorrect 12 ms 3024 KB Output isn't correct
43 Incorrect 10 ms 3676 KB Output isn't correct
44 Incorrect 33 ms 5884 KB Output isn't correct
45 Incorrect 10 ms 2908 KB Output isn't correct
46 Incorrect 41 ms 4188 KB Output isn't correct
47 Incorrect 36 ms 6992 KB Output isn't correct
48 Incorrect 19 ms 6704 KB Output isn't correct
49 Incorrect 35 ms 4284 KB Output isn't correct
50 Correct 219 ms 1768 KB Output is correct