oj.uz

Submission #802392

# Submission time Handle Problem Language Result Execution time Memory
802392 2023-08-02T12:05:28 Z boris_mihov Highway Tolls (IOI18_highway) C++17
39 / 100
 1500 ms 18196 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;
    assert(cnt2 != 0);
    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);
        if (res > 1LL * a * cnt + 1LL * b * cnt2) l = mid;
        else r = mid;
    }
    
    std::fill(w.begin(), w.end(), 1);
    for (int i = 0 ; i < order.size() ; ++i)
    {
        w[order[i]] = 0;
    }

    llong res = ask(w);
    while (res != 1LL * cnt * a + 1LL * cnt2 * b || r == order.size());
    assert(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();

        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])
        {
            toAsk[idx] = 1;
        }
    }
    std::fill(toAsk.begin(), toAsk.end(), 0);
    for (int i = 0 ; i < n ; ++i)
    {
        for (const auto &[u, idx] : t1[i])
        {
            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:76:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   76 |     for (int i = 0 ; i < order.size() ; ++i)
      |                      ~~^~~~~~~~~~~~~~
highway.cpp:82:55: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   82 |     while (res != 1LL * cnt * a + 1LL * cnt2 * b || r == order.size());
      |                                                     ~~^~~~~~~~~~~~~~~
In file included from /usr/include/c++/10/cassert:44,
                 from highway.cpp:5:
highway.cpp:83:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |     assert(r < order.size());
      |            ~~^~~~~~~~~~~~~~

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6608 KB Output is correct
2 Correct 4 ms 6608 KB Output is correct
3 Correct 4 ms 6608 KB Output is correct
4 Correct 3 ms 6608 KB Output is correct
5 Correct 3 ms 6608 KB Output is correct
6 Correct 3 ms 6608 KB Output is correct
7 Correct 3 ms 6608 KB Output is correct
8 Execution timed out 3036 ms 6652 KB Time limit exceeded
9 Halted 0 ms 0 KB -

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 6784 KB Output is correct
2 Correct 13 ms 7852 KB Output is correct
3 Correct 161 ms 17496 KB Output is correct
4 Correct 125 ms 17552 KB Output is correct
5 Correct 156 ms 17504 KB Output is correct
6 Correct 138 ms 17476 KB Output is correct
7 Correct 110 ms 17512 KB Output is correct
8 Correct 121 ms 17520 KB Output is correct
9 Execution timed out 3079 ms 17540 KB Time limit exceeded
10 Halted 0 ms 0 KB -

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 7756 KB Output is correct
2 Correct 18 ms 8812 KB Output is correct
3 Correct 31 ms 9748 KB Output is correct
4 Correct 85 ms 16244 KB Output is correct
5 Correct 72 ms 16248 KB Output is correct
6 Correct 82 ms 16300 KB Output is correct
7 Correct 64 ms 15956 KB Output is correct
8 Correct 63 ms 16264 KB Output is correct
9 Correct 84 ms 16236 KB Output is correct

Subtask #4
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 6736 KB Output is correct
2 Correct 14 ms 7808 KB Output is correct
3 Correct 69 ms 15164 KB Output is correct
4 Correct 108 ms 17516 KB Output is correct
5 Correct 102 ms 17544 KB Output is correct
6 Correct 108 ms 17488 KB Output is correct
7 Correct 97 ms 17008 KB Output is correct
8 Correct 102 ms 17504 KB Output is correct
9 Correct 103 ms 17448 KB Output is correct
10 Correct 119 ms 17472 KB Output is correct
11 Correct 107 ms 16376 KB Output is correct
12 Correct 128 ms 16360 KB Output is correct
13 Correct 131 ms 16328 KB Output is correct
14 Correct 103 ms 16260 KB Output is correct
15 Correct 113 ms 17524 KB Output is correct
16 Correct 100 ms 17496 KB Output is correct
17 Correct 100 ms 16356 KB Output is correct
18 Correct 115 ms 16364 KB Output is correct
19 Correct 111 ms 17496 KB Output is correct
20 Correct 94 ms 16600 KB Output is correct
21 Correct 100 ms 18184 KB Output is correct
22 Correct 109 ms 18196 KB Output is correct
23 Correct 101 ms 18176 KB Output is correct
24 Correct 112 ms 17776 KB Output is correct
25 Correct 101 ms 16540 KB Output is correct

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Execution timed out 3029 ms 7752 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 31.0

# Verdict Execution time Memory Grader output
1 Execution timed out 3031 ms 7848 KB Time limit exceeded
2 Halted 0 ms 0 KB -