Submission #725105

#	Time	Username	Problem	Language	Result	Execution time	Memory
725105		danikoynov	Fun Tour (APIO20_fun)	C++14	66 / 100	231 ms	38904 KiB

fun

#include "fun.h"

#include <bits/stdc++.h>
using namespace std;

const int maxn = 2e6 + 10;

int sub[maxn], dis[maxn];

bool cmp(int a, int b)
{
    return dis[a] < dis[b];
}
vector<int> createFunTour(int N, int Q)
{
    for (int i = 0; i < N; i ++)
        sub[i] = attractionsBehind(0, i);

    int centroid = 0;
    for (int i = 0; i < N; i ++)
    {
        if (sub[i] >= (N + 1) / 2 && sub[i] < sub[centroid])
            centroid = i;
    }

    for (int i = 0; i < N; i ++)
        dis[i] = hoursRequired(centroid, i);

    vector < int > cp[3];
    int p[3];
    p[0] = p[1] = p[2] = -1;
    for (int i = 0; i < N; i ++)
    {
        if (dis[i] == 1)
        {
            if (p[0] == -1)
                p[0] = i;
            else if (p[1] == -1)
                p[1] = i;
            else
                p[2] = i;
        }
    }


    for (int i = 0; i < N; i ++)
    {
        if (i == centroid)
            continue;
        if (i == p[0])
            cp[0].push_back(i);
        else if (i == p[1])
            cp[1].push_back(i);
        else if (i == p[2])
            cp[2].push_back(i);
        else
        {
            if (hoursRequired(p[0], i) + 1 == dis[i])
                cp[0].push_back(i);
            else if (hoursRequired(p[1], i) + 1 == dis[i])
                cp[1].push_back(i);
            else
                cp[2].push_back(i);
        }
    }

    /**for (int v : cp[0])
        cout << v << " ";
    cout << endl;
    for (int v : cp[1])
        cout << v << " ";
    cout << endl;
        for (int v : cp[2])
        cout << v << " ";
    cout << endl;*/

    if (cp[0].size() < cp[1].size())
    {
        swap(p[0], p[1]);
        swap(cp[0], cp[1]);
    }

    if (cp[0].size() < cp[2].size())
    {
        swap(p[0], p[2]);
        swap(cp[0], cp[2]);
    }

    if (cp[1].size() < cp[2].size())
    {
        swap(p[1], p[2]);
        swap(cp[1], cp[2]);
    }

    sort(cp[0].begin(), cp[0].end(), cmp);
    sort(cp[1].begin(), cp[1].end(), cmp);
    sort(cp[2].begin(), cp[2].end(), cmp);
    vector < int > ans;
    int last = -1;
    if (p[2] == -1)
    {
        while(cp[1].size() > 0)
        {
            ans.push_back(cp[0].back());
            ans.push_back(cp[1].back());
            cp[0].pop_back();
            cp[1].pop_back();
        }
        if (!cp[0].empty())
            ans.push_back(cp[0].back());
    }
    else
    {
        int big = -1;
        while(true)
        {
            if (cp[0].size() == cp[1].size() + cp[2].size())
            {
                big = 0;
                break;
            }
            if (cp[1].size() == cp[0].size() + cp[2].size())
            {
                big = 1;
                break;
            }
            if (cp[2].size() == cp[0].size() + cp[1].size())
            {
                big = 2;
                break;
            }

            int cur = -1;
            if (last != 0 && (cur == -1 || dis[cp[0].back()] > dis[cp[cur].back()]))
                cur = 0;
            if (last != 1 && (cur == -1 || dis[cp[1].back()] > dis[cp[cur].back()]))
                cur = 1;
                if (last != 2 && (cur == -1 || dis[cp[2].back()] > dis[cp[cur].back()]))
                cur = 2;

            ans.push_back(cp[cur].back());
            cp[cur].pop_back();
            last = cur;
        }

        vector < int > sm;
        for (int i = 0; i < 3; i ++)
        {
            if (i != big)
                sm.push_back(i);
        }

        int v = sm[0], u = sm[1];
        if (v == last)
            v = sm[1], u = sm[0];

        if (dis[cp[v].back()] > dis[cp[u].back()])
            last = big;
        while(!cp[v].empty())
        {
            cp[u].push_back(cp[v].back());
            cp[v].pop_back();
        }
    if (cp[big].size() != cp[u].size())
    {
        while(true);
        cout << 1 / 0 << endl;
        exit(0);
    }
        sort(cp[u].begin(), cp[u].end(), cmp);
        while(ans.size() < N - 1)
        {
            if (last == big)
            {
                ans.push_back(cp[u].back());
                cp[u].pop_back();
                last = u;
            }
            else
            {
                ans.push_back(cp[big].back());
                cp[big].pop_back();
                last = big;
            }
        }

    }


    ans.push_back(centroid);
    /*cout << "tour" << endl;
    for (int v : ans)
        cout << v << " ";
    cout << endl;*/
    return ans;
}

Compilation message (stderr)

fun.cpp: In function 'std::vector<int> createFunTour(int, int)':
fun.cpp:136:13: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  136 |             if (last != 1 && (cur == -1 || dis[cp[1].back()] > dis[cp[cur].back()]))
      |             ^~
fun.cpp:138:17: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  138 |                 if (last != 2 && (cur == -1 || dis[cp[2].back()] > dis[cp[cur].back()]))
      |                 ^~
fun.cpp:167:19: warning: division by zero [-Wdiv-by-zero]
  167 |         cout << 1 / 0 << endl;
      |                 ~~^~~
fun.cpp:171:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  171 |         while(ans.size() < N - 1)
      |               ~~~~~~~~~~~^~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 16 / 16
• Subtask 3: 21 / 21
• Subtask 4: 19 / 19
• Subtask 5: 0 / 34