Submission #927899

#	Time	Username	Problem	Language	Result	Execution time	Memory
927899		aykhn	Longest Trip (IOI23_longesttrip)	C++17	60 / 100	816 ms	1368 KiB

longesttrip

#include <bits/stdc++.h>
#include "longesttrip.h"
 
using namespace std;
 
int A[300][300];
 
int ask(vector<int> a, vector<int> b)
{
    for (int x : a)
    {
        for (int y : b)
        {
            if (A[x][y]) return 1;
        }
    }
    return 0;
}
 
vector<int> longest_trip(int n, int D)
{
    int c = 0;
    for (int i = 0; i < n; i++)
    {
        A[i][i] = 1;
        for (int j = i + 1; j < n; j++)
        {
            A[i][j] = A[j][i] = are_connected({i}, {j});
        }
    }
    vector<int> used(n, 0);
    vector<int> v1, v2;
    for (int i = 0; i < 3; i++)
    {
        for (int j = i + 1; j < 3; j++)
        {
            if (ask({i}, {j}))
            {
                v1.push_back(i), v1.push_back(j);
                used[i] = used[j] = 1;
                break;
            }
        }
        if (!v1.empty()) break;
    }
    for (int i = 0; i < n; i++)
    {
        if (used[i]) continue;
        used[i] = 1;
        if (ask(v1, {i}) && ask(v2, {i})) 
        {
            assert(++c <= 1);
            int id1 = -1, id2 = -1;
            for (int j = 0; j < v1.size(); j++)
            {
                if (ask({v1[j]}, {i}))
                {
                    id1 = j;
                    break;
                }
            }
            for (int j = 0; j < v2.size(); j++)
            {
                if (ask({v2[j]}, {i}))
                {
                    id2 = j;
                    break;
                }
            }
            assert(id1 != -1 && id2 != -1);
            vector<int> nw;
            for (int j = (id2 + 1) % v2.size(); 1; j = (j + 1) % v2.size())
            {
                nw.push_back(v2[j]);
                if (j == id2) break;
            }
            nw.push_back(i), nw.push_back(v1[id1]);
            for (int j = (id1 + 1) % v1.size(); j != id1; j = (j + 1) % v1.size())
            {
                nw.push_back(v1[j]);
            }
            v2.clear();
            v1 = nw;
        }
        else if (ask(v1, {i})) 
        {
            vector<int> nw;
            int idx = -1;
            if (ask({v1[0]}, {i})) 
            {
                nw.push_back(i);
                for (int x : v1) nw.push_back(x);
            }
            else if (ask({v1.back()}, {i}))
            {
                nw = v1;
                nw.push_back(i);
            }
            else
            {
                for (int j = 0; j < v1.size(); j++) 
                {
                    if (ask({i}, {v1[j]})) 
                    {
                        idx = j;
                        break;
                    }
                }
                nw.push_back(i), nw.push_back(v1[idx]);
                for (int j = (idx + 1) % v1.size(); j != idx; j = (j + 1) % v1.size())
                {
                    nw.push_back(v1[j]);
                }
            }
            v1 = nw;
        }
        else if (ask(v2, {i}))
        {
            vector<int> nw;
            int idx = -1;
            if (ask({v2[0]}, {i})) 
            {
                nw.push_back(i);
                for (int x : v2) nw.push_back(x);
            }
            else if (ask({v2.back()}, {i}))
            {
                nw = v2;
                nw.push_back(i);
            }
            else
            {
                for (int j = 0; j < v2.size(); j++) 
                {
                    if (ask({i}, {v2[j]})) 
                    {
                        idx = j;
                        break;
                    }
                }
                nw.push_back(i), nw.push_back(v2[idx]);
                for (int j = (idx + 1) % v2.size(); j != idx; j = (j + 1) % v2.size())
                {
                    nw.push_back(v2[j]);
                }
            }
            v2 = nw;
        }
        else v2.push_back(i);
    }
    if (v1.size() > v2.size()) return v1;
    else return v2;
};

Compilation message (stderr)

longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:54:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |             for (int j = 0; j < v1.size(); j++)
      |                             ~~^~~~~~~~~~~
longesttrip.cpp:62:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |             for (int j = 0; j < v2.size(); j++)
      |                             ~~^~~~~~~~~~~
longesttrip.cpp:101:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  101 |                 for (int j = 0; j < v1.size(); j++)
      |                                 ~~^~~~~~~~~~~
longesttrip.cpp:133:35: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  133 |                 for (int j = 0; j < v2.size(); j++)
      |                                 ~~^~~~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 25 / 25
• Subtask 4: 19.999999998 / 60