oj.uz

Submission #1027690

# Submission time Handle Problem Language Result Execution time Memory
1027690 2024-07-19T09:08:57 Z caterpillow Marriage questions (IZhO14_marriage) C++17
66 / 100
 183 ms 3132 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<vt<int>> adj; // l -> r
vt<int> mni; // index of first neighbour we iterate over
vt<int> mate; // mate = rhs -> lhs
bool seen[2001]; // seen of lhs

bool dfs(int u) {
    if (seen[u]) return false;
    seen[u] = true;
    FOR (i, mni[u], size(adj[u])) {
        int v = adj[u][i];
        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);
    mni.resize(m);
    mate.resize(m, -1);

    vt<pi> edges;
    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);
    }

    int r = 0, matches = 0;
    vt<int> mxr(m, m + 1); // exc
    queue<int> to_match;
    F0R (i, n) to_match.push(i);
    F0R (l, m) {
        while (size(to_match)) {
            if (r == m) break;
            // add these edges
            for (int u : radj[r]) adj[u].pb(r);
            // try augment
            int u = to_match.front();
            memset(seen, 0, sizeof(seen));
            while (dfs(u)) {
                to_match.pop();
                if (!size(to_match)) break;
                u = to_match.front();
                memset(seen, 0, sizeof(seen));
            }
            r++; 
        }
        if (size(to_match)) break;
        mxr[l] = r;
        // remove edges
        for (int u : radj[l]) {
            mni[u]++;
        }
        // check if we unmatched someone
        if (mate[l] != -1) {
            to_match.push(mate[l]);
            mate[l] = -1;
        }
    }
    ll ans = 0;
    F0R (i, m) ans += m - mxr[i] + 1;
    cout << ans << endl;
}

Compilation message

marriage.cpp:100:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  100 | main() {
      | ^~~~
marriage.cpp: In function 'int main()':
marriage.cpp:116:16: warning: unused variable 'matches' [-Wunused-variable]
  116 |     int r = 0, matches = 0;
      |                ^~~~~~~

Subtask #1
66.0 / 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 1 ms 348 KB Output is correct
4 Correct 0 ms 348 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 Correct 0 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 0 ms 348 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 348 KB Output is correct
15 Incorrect 0 ms 344 KB Output isn't 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 472 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 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 3 ms 600 KB Output is correct
26 Incorrect 1 ms 344 KB Output isn't correct
27 Correct 0 ms 344 KB Output is correct
28 Correct 0 ms 344 KB Output is correct
29 Incorrect 2 ms 348 KB Output isn't correct
30 Incorrect 1 ms 348 KB Output isn't correct
31 Correct 27 ms 972 KB Output is correct
32 Incorrect 2 ms 604 KB Output isn't correct
33 Correct 0 ms 348 KB Output is correct
34 Correct 4 ms 348 KB Output is correct
35 Correct 20 ms 1568 KB Output is correct
36 Correct 20 ms 1368 KB Output is correct
37 Correct 82 ms 1224 KB Output is correct
38 Incorrect 13 ms 1628 KB Output isn't correct
39 Correct 83 ms 1120 KB Output is correct
40 Correct 3 ms 1116 KB Output is correct
41 Incorrect 5 ms 1116 KB Output isn't correct
42 Incorrect 5 ms 1372 KB Output isn't correct
43 Incorrect 7 ms 1624 KB Output isn't correct
44 Incorrect 11 ms 2136 KB Output isn't correct
45 Incorrect 11 ms 2392 KB Output isn't correct
46 Incorrect 81 ms 2968 KB Output isn't correct
47 Incorrect 16 ms 2904 KB Output isn't correct
48 Incorrect 14 ms 2908 KB Output isn't correct
49 Incorrect 91 ms 3132 KB Output isn't correct
50 Correct 183 ms 1740 KB Output is correct