oj.uz

Submission #802367

# Submission time Handle Problem Language Result Execution time Memory
802367 2023-08-02T11:56:45 Z boris_mihov Highway Tolls (IOI18_highway) C++17
39 / 100
 146 ms 34404 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;
    }

    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

In file included from /usr/include/c++/10/cassert:44,
                 from highway.cpp:5:
highway.cpp: In function 'int find(std::vector<std::pair<int, int> >*, int, int, int)':
highway.cpp:74:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |     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 6652 KB Output is correct
5 Correct 3 ms 6608 KB Output is correct
6 Correct 2 ms 6608 KB Output is correct
7 Correct 4 ms 6608 KB Output is correct
8 Runtime error 8 ms 13312 KB Execution killed with signal 6
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 7760 KB Output is correct
3 Correct 114 ms 17488 KB Output is correct
4 Correct 115 ms 17504 KB Output is correct
5 Correct 127 ms 17504 KB Output is correct
6 Correct 101 ms 17516 KB Output is correct
7 Correct 99 ms 17496 KB Output is correct
8 Correct 107 ms 17508 KB Output is correct
9 Runtime error 112 ms 34404 KB Execution killed with signal 6
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 18 ms 8824 KB Output is correct
3 Correct 39 ms 9748 KB Output is correct
4 Correct 68 ms 16236 KB Output is correct
5 Correct 72 ms 16256 KB Output is correct
6 Correct 106 ms 16296 KB Output is correct
7 Correct 99 ms 15952 KB Output is correct
8 Correct 86 ms 16268 KB Output is correct
9 Correct 68 ms 16120 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 15 ms 7760 KB Output is correct
3 Correct 85 ms 15156 KB Output is correct
4 Correct 95 ms 17500 KB Output is correct
5 Correct 90 ms 17536 KB Output is correct
6 Correct 101 ms 17480 KB Output is correct
7 Correct 111 ms 17012 KB Output is correct
8 Correct 113 ms 17492 KB Output is correct
9 Correct 106 ms 17456 KB Output is correct
10 Correct 114 ms 17480 KB Output is correct
11 Correct 109 ms 16388 KB Output is correct
12 Correct 114 ms 16352 KB Output is correct
13 Correct 132 ms 16416 KB Output is correct
14 Correct 146 ms 16272 KB Output is correct
15 Correct 120 ms 17508 KB Output is correct
16 Correct 104 ms 17476 KB Output is correct
17 Correct 116 ms 16368 KB Output is correct
18 Correct 121 ms 16376 KB Output is correct
19 Correct 121 ms 17488 KB Output is correct
20 Correct 138 ms 16480 KB Output is correct
21 Correct 128 ms 18188 KB Output is correct
22 Correct 100 ms 18196 KB Output is correct
23 Correct 132 ms 17944 KB Output is correct
24 Correct 134 ms 17776 KB Output is correct
25 Correct 111 ms 16544 KB Output is correct

Subtask #5
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 7844 KB Output is correct
2 Incorrect 12 ms 7940 KB Output is incorrect: {s, t} is wrong.
3 Halted 0 ms 0 KB -

Subtask #6
0 / 31.0

# Verdict Execution time Memory Grader output
1 Runtime error 21 ms 15984 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -