답안 #802338

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
802338 2023-08-02T11:43:24 Z boris_mihov 통행료 (IOI18_highway) C++17
39 / 100
163 ms 18244 KB
#include "highway.h"
#include <algorithm>
#include <iostream>
#include <numeric>
#include <cassert>
#include <numeric>
#include <vector>
#include <queue>

typedef long long llong;
const int MAXN = 90000 + 10;
const llong INF = 1e18;
const int INTINF = 1e9;

int n, m, a, b;
std::queue <int> q;
std::vector <std::pair <int,int>> g[MAXN];
std::vector <std::pair <int,int>> t1[MAXN];
std::vector <std::pair <int,int>> t2[MAXN];
std::vector <int> edgeU;
std::vector <int> edgeV;
int inTree[MAXN];
bool vis[MAXN];
int par[MAXN];

int find(std::vector <std::pair <int,int>> t[], int root, int cnt, int cnt2)
{
    // std::cout << "find: " << root << ' ' << cnt << '\n' << std::flush;
    if (cnt == 0)
    {
        return root;
    }

    while (!q.empty())
    {
        q.pop();
    }

    std::vector <int> order;
    q.push(root);

    while (!q.empty())
    {
        int top = q.front();
        q.pop();

        for (const auto &[u, idx] : t[top])
        {
            if (u != par[top])
            {
                order.push_back(idx);
                q.push(u);
            }
        }
    }

    std::vector <int> w(m);
    int l = -1, r = order.size(), mid;
    while (l < r - 1)
    {
        mid = (l + r) / 2;
        std::fill(w.begin(), w.end(), 1);

        for (int i = 0 ; i <= mid ; ++i)
        {
            w[order[i]] = 0;
        }

        llong res = ask(w);
        // std::cout << "here: " << mid << ' ' << res << ' ' << 1LL * a * cnt + 1LL * b * cnt2 << '\n';
        if (res > 1LL * a * cnt + 1LL * b * cnt2) l = mid;
        else r = mid;
    }

    while (r == order.size());
    int u = edgeU[order[r]];
    int v = edgeV[order[r]];
    if (par[v] == u)
    {
        std::swap(u, v);
    }

    return u;
}

void find_pair(int N, std::vector<int> U, std::vector<int> V, int A, int B) 
{
    n = N;
    m = U.size();
    a = A; b = B;
    edgeU = U;
    edgeV = V;

    for (int i = 0 ; i < m ; ++i)
    {
        g[U[i]].push_back({V[i], i});
        g[V[i]].push_back({U[i], i});
    }

    std::vector <int> toAsk(m, 0);
    llong res = ask(toAsk);

    int l = -1, r = m, mid;
    while (l < r - 1)
    {
        mid = (l + r) / 2;
        std::fill(toAsk.begin(), toAsk.end(), 0);
        for (int i = 0 ; i <= mid ; ++i)
        {
            toAsk[i] = 1;
        }

        llong curr = ask(toAsk);
        if (curr == res) l = mid;
        else r = mid;
    }

    assert(r < m);
    int rootOne = U[r];
    int rootTwo = V[r];
    inTree[rootOne] = 1;
    inTree[rootTwo] = 2;
    vis[rootOne] = true;
    vis[rootTwo] = true;
    q.push(rootOne);
    q.push(rootTwo);

    while (!q.empty())
    {
        int top = q.front();
        q.pop();

        // std::cout << "top: " << top << ' ' << inTree[top] << '\n';
        for (const auto &[u, idx] : g[top])
        {
            if (!vis[u])
            {
                par[u] = top;
                vis[u] = true;
                inTree[u] = inTree[top];
                if (inTree[top] == 1)
                {
                    t1[top].push_back({u, idx});
                    t1[u].push_back({top, idx});
                } else
                {
                    t2[top].push_back({u, idx});
                    t2[u].push_back({top, idx});
                }

                q.push(u);
            }
        }
    }       

    std::fill(toAsk.begin(), toAsk.end(), 0);
    for (int i = 0 ; i < n ; ++i)
    {
        for (const auto &[u, idx] : t1[i])
        {
            // std::cout << "idx: " << idx << '\n';
            toAsk[idx] = 1;
        }
    }

    // std::cout << "EDGE: " << rootOne << ' ' << rootTwo << '\n';
    // std::cout << "treeONE\n";
    // for (int i = 0 ; i < m ; ++i)
    // {
    //     if (toAsk[i] == 1)
    //     {
    //         std::cout << i + 1 << ' ';
    //     }
    // }
    
    // std::cout << '\n';
    
    // std::fill(toAsk.begin(), toAsk.end(), 0);
    // for (int i = 0 ; i < n ; ++i)
    // {
    //     for (const auto &[u, idx] : t2[i])
    //     {
    //         std::cout << "idx: " << idx << '\n';
    //         toAsk[idx] = 1;
    //     }
    // }

    // std::cout << "treeTWO\n";
    // for (int i = 0 ; i < m ; ++i)
    // {
    //     if (toAsk[i] == 1)
    //     {
    //         std::cout << i + 1 << ' ';
    //     }
    // }

    // std::cout << "in tree\n" << std::flush;
    // for (int i = 0 ; i < n ; ++i)
    // {
    //     std::cout << inTree[i] << ' ';
    // }

    // std::cout << '\n';
    std::fill(toAsk.begin(), toAsk.end(), 0);
    for (int i = 0 ; i < n ; ++i)
    {
        for (const auto &[u, idx] : t1[i])
        {
            // std::cout << "idx: " << idx << '\n';
            toAsk[idx] = 1;
        }
    }

    llong currRES = ask(toAsk);
    int cntEdges = (currRES - res) / (b - a);
    int cntEdges2 = res / a - cntEdges - 1;
    int s = find(t1, rootOne, cntEdges, cntEdges2 + 1);
    int t = find(t2, rootTwo, cntEdges2, cntEdges + 1);
    answer(s, t);
}

/*
9 12 1 10 1 3
0 1
1 2
2 6
6 3
3 4
4 0
0 5
5 6
6 7
7 0
0 8
8 6
*/

Compilation message

highway.cpp: In function 'int find(std::vector<std::pair<int, int> >*, int, int, int)':
highway.cpp:75:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |     while (r == order.size());
      |            ~~^~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 6608 KB Output is correct
2 Correct 3 ms 6608 KB Output is correct
3 Correct 3 ms 6608 KB Output is correct
4 Correct 3 ms 6608 KB Output is correct
5 Correct 4 ms 6608 KB Output is correct
6 Correct 3 ms 6608 KB Output is correct
7 Correct 4 ms 6652 KB Output is correct
8 Incorrect 3 ms 6656 KB Output is incorrect: {s, t} is wrong.
9 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 6736 KB Output is correct
2 Correct 13 ms 7800 KB Output is correct
3 Correct 104 ms 17476 KB Output is correct
4 Correct 122 ms 17524 KB Output is correct
5 Correct 123 ms 17568 KB Output is correct
6 Correct 99 ms 17476 KB Output is correct
7 Correct 143 ms 17568 KB Output is correct
8 Correct 99 ms 17508 KB Output is correct
9 Incorrect 111 ms 17608 KB Output is incorrect: {s, t} is wrong.
10 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 7664 KB Output is correct
2 Correct 21 ms 8816 KB Output is correct
3 Correct 26 ms 9748 KB Output is correct
4 Correct 84 ms 16308 KB Output is correct
5 Correct 69 ms 16292 KB Output is correct
6 Correct 93 ms 16308 KB Output is correct
7 Correct 90 ms 15952 KB Output is correct
8 Correct 67 ms 16260 KB Output is correct
9 Correct 106 ms 16116 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 4 ms 6736 KB Output is correct
2 Correct 16 ms 7808 KB Output is correct
3 Correct 67 ms 15160 KB Output is correct
4 Correct 96 ms 17620 KB Output is correct
5 Correct 145 ms 17480 KB Output is correct
6 Correct 80 ms 17476 KB Output is correct
7 Correct 109 ms 17032 KB Output is correct
8 Correct 84 ms 17488 KB Output is correct
9 Correct 99 ms 17452 KB Output is correct
10 Correct 141 ms 17476 KB Output is correct
11 Correct 121 ms 16380 KB Output is correct
12 Correct 103 ms 16352 KB Output is correct
13 Correct 110 ms 16312 KB Output is correct
14 Correct 123 ms 16268 KB Output is correct
15 Correct 99 ms 17588 KB Output is correct
16 Correct 116 ms 17492 KB Output is correct
17 Correct 112 ms 16352 KB Output is correct
18 Correct 91 ms 16368 KB Output is correct
19 Correct 109 ms 17572 KB Output is correct
20 Correct 92 ms 16388 KB Output is correct
21 Correct 88 ms 18188 KB Output is correct
22 Correct 95 ms 18244 KB Output is correct
23 Correct 124 ms 17924 KB Output is correct
24 Correct 109 ms 17772 KB Output is correct
25 Correct 163 ms 16544 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 14 ms 7880 KB Output is correct
2 Incorrect 13 ms 7956 KB Output is incorrect: {s, t} is wrong.
3 Halted 0 ms 0 KB -
# 결과 실행 시간 메모리 Grader output
1 Incorrect 13 ms 7880 KB Output is incorrect: {s, t} is wrong.
2 Halted 0 ms 0 KB -