oj.uz

Submission #1027764

# Submission time Handle Problem Language Result Execution time Memory
1027764 2024-07-19T09:45:35 Z caterpillow Marriage questions (IZhO14_marriage) C++17
100 / 100
 534 ms 6236 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)) {
                // 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() {
      |     ^~~~

Subtask #1
100.0 / 100.0

# Verdict Execution time Memory 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