oj.uz

Submission #1027723

# Submission time Handle Problem Language Result Execution time Memory
1027723 2024-07-19T09:27:01 Z caterpillow Marriage questions (IZhO14_marriage) C++17
64 / 100
 180 ms 7208 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]) assert(adj[u].insert(r).s);

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

        // add # of possible right endpoints for l
        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;
        }
    }
}

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 0 ms 348 KB Output isn't correct
2 Incorrect 1 ms 348 KB Output isn't correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 456 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 0 ms 452 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 456 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Incorrect 1 ms 348 KB Output isn't correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 604 KB Output is correct
17 Correct 0 ms 452 KB Output is correct
18 Correct 1 ms 344 KB Output is correct
19 Correct 1 ms 348 KB Output is correct
20 Correct 1 ms 388 KB Output is correct
21 Correct 0 ms 348 KB Output is correct
22 Correct 0 ms 348 KB Output is correct
23 Correct 1 ms 456 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 3 ms 604 KB Output is correct
26 Incorrect 1 ms 348 KB Output isn't correct
27 Correct 0 ms 348 KB Output is correct
28 Correct 0 ms 348 KB Output is correct
29 Incorrect 2 ms 824 KB Output isn't correct
30 Incorrect 3 ms 860 KB Output isn't correct
31 Correct 61 ms 2228 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 5 ms 604 KB Output is correct
35 Correct 15 ms 5692 KB Output is correct
36 Correct 15 ms 4832 KB Output is correct
37 Correct 90 ms 2208 KB Output is correct
38 Incorrect 26 ms 6176 KB Output isn't correct
39 Correct 79 ms 1220 KB Output is correct
40 Correct 5 ms 1492 KB Output is correct
41 Incorrect 7 ms 1884 KB Output isn't correct
42 Incorrect 8 ms 2904 KB Output isn't correct
43 Incorrect 12 ms 3604 KB Output isn't correct
44 Incorrect 20 ms 6200 KB Output isn't correct
45 Incorrect 10 ms 3100 KB Output isn't correct
46 Incorrect 29 ms 4444 KB Output isn't correct
47 Incorrect 19 ms 7208 KB Output isn't correct
48 Incorrect 18 ms 6748 KB Output isn't correct
49 Incorrect 30 ms 4368 KB Output isn't correct
50 Correct 180 ms 1904 KB Output is correct