oj.uz

Submission #802390

# Submission time Handle Problem Language Result Execution time Memory
802390 2023-08-02T12:04:23 Z boris_mihov Highway Tolls (IOI18_highway) C++17
39 / 100
 1500 ms 18240 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);
        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:75:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   75 |     for (int i = 0 ; i < order.size() ; ++i)
      |                      ~~^~~~~~~~~~~~~~
highway.cpp:81:55: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |     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:82:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   82 |     assert(r < order.size());
      |            ~~^~~~~~~~~~~~~~

Subtask #1
0 / 5.0

# Verdict Execution time Memory 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 3 ms 6608 KB Output is correct
8 Execution timed out 3047 ms 6608 KB Time limit exceeded
9 Halted 0 ms 0 KB -

Subtask #2
0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 6736 KB Output is correct
2 Correct 13 ms 7836 KB Output is correct
3 Correct 103 ms 17484 KB Output is correct
4 Correct 118 ms 17512 KB Output is correct
5 Correct 117 ms 17516 KB Output is correct
6 Correct 104 ms 17488 KB Output is correct
7 Correct 103 ms 17504 KB Output is correct
8 Correct 114 ms 17592 KB Output is correct
9 Execution timed out 3025 ms 17496 KB Time limit exceeded
10 Halted 0 ms 0 KB -

Subtask #3
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 7632 KB Output is correct
2 Correct 19 ms 8828 KB Output is correct
3 Correct 24 ms 9744 KB Output is correct
4 Correct 84 ms 16348 KB Output is correct
5 Correct 64 ms 16248 KB Output is correct
6 Correct 83 ms 16304 KB Output is correct
7 Correct 87 ms 16072 KB Output is correct
8 Correct 80 ms 16264 KB Output is correct
9 Correct 69 ms 16124 KB Output is correct

Subtask #4
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 6704 KB Output is correct
2 Correct 14 ms 7804 KB Output is correct
3 Correct 75 ms 15256 KB Output is correct
4 Correct 97 ms 17508 KB Output is correct
5 Correct 105 ms 17480 KB Output is correct
6 Correct 93 ms 17616 KB Output is correct
7 Correct 80 ms 16968 KB Output is correct
8 Correct 96 ms 17596 KB Output is correct
9 Correct 124 ms 17448 KB Output is correct
10 Correct 104 ms 17468 KB Output is correct
11 Correct 110 ms 16484 KB Output is correct
12 Correct 97 ms 16356 KB Output is correct
13 Correct 131 ms 16352 KB Output is correct
14 Correct 102 ms 16268 KB Output is correct
15 Correct 98 ms 17508 KB Output is correct
16 Correct 88 ms 17480 KB Output is correct
17 Correct 99 ms 16352 KB Output is correct
18 Correct 120 ms 16444 KB Output is correct
19 Correct 86 ms 17492 KB Output is correct
20 Correct 90 ms 16380 KB Output is correct
21 Correct 81 ms 18240 KB Output is correct
22 Correct 88 ms 18164 KB Output is correct
23 Correct 106 ms 17932 KB Output is correct
24 Correct 115 ms 17768 KB Output is correct
25 Correct 120 ms 16528 KB Output is correct

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Execution timed out 3006 ms 7744 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 3029 ms 7848 KB Time limit exceeded
2 Halted 0 ms 0 KB -