답안 #842903

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
842903 2023-09-03T13:10:36 Z I_love_Hoang_Yen 봉쇄 시간 (IOI23_closing) C++17
26 / 100
149 ms 45160 KB
#include "closing.h"
#include <algorithm>
#include <set>
#include <vector>
#include <cassert>
using namespace std;
 
using ll = long long;
using Graph = vector<vector<pair<int,ll>>>;
 
void dfs(int u, int fu, const Graph& g, vector<ll>& dists, vector<int>& trace) {
    for (auto [v, w] : g[u]) {
        if (v == fu) continue;
        assert(dists[v] < 0);
 
        dists[v] = dists[u] + w;
        trace[v] = u;
        dfs(v, u, g, dists, trace);
    }
}
 
pair<vector<ll>, vector<int>> get_dists(int u, const Graph& g) {
    int n = g.size();
    vector<ll> dists(n, -1);
    vector<int> trace(n, -1);
    dists[u] = 0;
 
    dfs(u, -1, g, dists, trace);
    return {dists, trace};
}
 
int no_common(ll k, const vector<ll>& dx, const vector<ll>& dy) {
    vector<ll> all;
    for (auto d : dx) all.push_back(d);
    for (auto d : dy) all.push_back(d);
    sort(all.begin(), all.end());
    int cnt = 0;
    for (auto d : all) {
        if (d <= k) {
            k -= d;
            ++cnt;
        } else break;
    }
    return cnt;
}
 
// linear graph
struct Event {
    ll cost;
    int i;
    int typ;  // 1 = SINGLE, 2 = PAIR
};
bool operator < (const Event& a, const Event& b) {
    return a.cost * (3 - a.typ) < b.cost * (3 - b.typ);
}
 
int sub9(int n, ll k, int x, int y,
        const vector<ll>& dx, const vector<ll>& dy,
        const vector<bool>& on_path) {
    int res = no_common(k, dx, dy);
 
    // 0 .. [xl .. x .. xr]
    //               [yl .. y .. yr] .. n-1
    // Now we only consider the case where [xl, xr] and [yl, yr] overlap
    // They must overlap at least one point between [x, y]
    int cur = 0;
    vector<int> taken(n, 0);
    vector<Event> events;
    // 1. For every vertex not in path x -> y
    for (int i = 0; i < n; ++i) {
        if (on_path[i]) continue;
        int a = min(dx[i], dy[i]);
        int b = max(dx[i], dy[i]);
        if (b - a >= a) {
            events.push_back({a, i, 1});
            events.push_back({b - a, i, 1});
        } else {
            events.push_back({b, i, 2});
        }
    }
    // 2. On path x -> y, every point must be visited by either x or y
    for (int i = 0; i < n; ++i) {
        if (!on_path[i]) continue;
        k -= min(dx[i], dy[i]);
        // Additionally, we can choose to visit from other point
        ++cur;
        events.push_back({llabs(dx[i] - dy[i]), i, 1});
        taken[i] = 1;
    }
 
    if (k >= 0) {
        sort(events.begin(), events.end());
 
        for (auto& event : events) {
            if (event.cost > k) break;
            k -= event.cost;
            cur += event.typ;
 
            taken[event.i] += event.typ;
            assert(taken[event.i] <= 2);
            event.typ = 0;
        }
        // Break "bundle"
        set<pair<ll, int>> costs;
        for (auto& event : events) {
            if (event.typ == 2) costs.insert({min(dx[event.i], dy[event.i]), event.i});
        }
        for (auto [cost, i] : costs) if (k >= cost) {
            k -= cost, ++cur;
            taken[i] = 1;
        }
 
        multiset<ll> ones, twos;
        for (int i = 0; i < n; ++i) {
            int a = min(dx[i], dy[i]);
            int b = max(dx[i], dy[i]);
            if (taken[i] == 2) {
                ones.insert(b - a);
            } else if (taken[i] == 1 && !on_path[i]) {
                ones.insert(a);
                twos.insert(b);
            } else if (taken[i] == 0) {
                twos.insert(b);
            }
        }
        while (ones.size() > 0 && twos.size() > 0) {
            auto it_one = std::prev(ones.end());
            auto it_two = twos.begin();
            auto cost = *it_two - *it_one;
            if (cost <= k) {
                k -= cost;
                ++cur;
                ones.erase(it_one);
                twos.erase(it_two);
            } else break;
        }
        res = max(res, cur);
    }
    return res;
}
 
int max_score(int n, int X, int Y, long long K,
              vector<int> U, vector<int> V, vector<int> W) {
    Graph g(n);
    assert(int(U.size()) == n-1);
    assert(int(V.size()) == n-1);
    assert(int(W.size()) == n-1);
    for (int i = 0; i < n - 1; i++) {
        int u = U[i];
        int v = V[i];
        int w = W[i];
        g[u].emplace_back(v, w);
        g[v].emplace_back(u, w);
    }
    if (X > Y) swap(X, Y);
 
    auto [distsX, traceX] = get_dists(X, g);
    auto [distsY, traceY] = get_dists(Y, g);
    vector<bool> on_path(n, false);
    int cur = Y;
    while (cur != X) {
        on_path[cur] = true;
        cur = traceX[cur];
    }
    on_path[X] = true;
    
    return sub9(n, K, X, Y, distsX, distsY, on_path);
}
# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 348 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 146 ms 44968 KB Output is correct
2 Correct 149 ms 45160 KB Output is correct
3 Correct 78 ms 2896 KB Output is correct
# 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 0 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
# 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 0 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 1 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Incorrect 0 ms 348 KB 1st lines differ - on the 1st token, expected: '171', found: '180'
15 Halted 0 ms 0 KB -
# 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 0 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 1 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Incorrect 0 ms 348 KB 1st lines differ - on the 1st token, expected: '171', found: '180'
15 Halted 0 ms 0 KB -
# 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 0 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 344 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 0 ms 600 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 Correct 0 ms 348 KB Output is correct
16 Correct 1 ms 544 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 0 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 0 ms 348 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
# 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 0 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 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Incorrect 0 ms 348 KB 1st lines differ - on the 1st token, expected: '171', found: '180'
16 Halted 0 ms 0 KB -
# 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 0 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 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Incorrect 0 ms 348 KB 1st lines differ - on the 1st token, expected: '171', found: '180'
16 Halted 0 ms 0 KB -
# 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 0 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 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Incorrect 0 ms 348 KB 1st lines differ - on the 1st token, expected: '171', found: '180'
16 Halted 0 ms 0 KB -
# 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 0 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 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Incorrect 0 ms 348 KB 1st lines differ - on the 1st token, expected: '171', found: '180'
16 Halted 0 ms 0 KB -