제출 #850274

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
850274		nvmdava	가장 긴 여행 (IOI23_longesttrip)	C++17	85 / 100	15 ms	956 KiB

longesttrip

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


vector<int> rng(vector<int>& a, int l, int r) {
    vector<int> res;
    for(int i = l; i <= r; ++i) res.push_back(a[i]);
    return res;
}

std::vector<int> longest_trip(int N, int D)
{
    if(D == 3) {
        vector<int> res(N);
        for(int i = 0; i < N; ++i)
            res[i] = i;
        return res;
    }
    if(D == 2) {
        vector<int> res = {0};
        for(int i = 1; i < N; ++i) {
            if(are_connected({res.back()}, {i})) {
                res.push_back(i);
                continue;
            }
            if(i == 1) {
                res.push_back(i + 1);
                res.push_back(i);
                i++;
                continue;
            }
            res.insert(res.begin(), i);
        }
        return res;
    }
    
    vector<vector<int> > all;
    for(int i = 0; i < N; ++i) {
        all.push_back({i});
    }
    bool la = 0;
    while(all.size() >= 3) {
        int sz = all.size();
        if(la == 0) {
            if(are_connected({all[sz - 1].back()}, {all[sz - 2].back()})) {
                reverse(all[sz - 1].begin(), all[sz - 1].end());
                for(auto x : all[sz - 1]) all[sz - 2].push_back(x);
                all.pop_back();
                la = 0;
                continue;
            }
            la = 1;
        }
        if(are_connected({all[sz - 1].back()}, {all[sz - 3].back()})) {
            reverse(all[sz - 1].begin(), all[sz - 1].end());
            for(auto x : all[sz - 1]) all[sz - 3].push_back(x);
            all.pop_back();
            la = 0;
            continue;
        }
        reverse(all[sz - 2].begin(), all[sz - 2].end());
        for(auto x : all[sz - 2]) all[sz - 3].push_back(x);
        swap(all[sz - 1], all[sz - 2]);
        all.pop_back();
        la = 0;
    }


    if(are_connected({all[0].back()}, {all[1].back()})) {
        reverse(all[1].begin(), all[1].end());
        for(auto x : all[1]) all[0].push_back(x);
        return all[0];
    }

    if(are_connected({all[0].back()}, {all[1][0]})) {
        for(auto x : all[1]) all[0].push_back(x);
        return all[0];
    }

    if(are_connected({all[0][0]}, {all[1][0]})) {
        reverse(all[0].begin(), all[0].end());
        for(auto x : all[1]) all[0].push_back(x);
        return all[0];
    }

    if(are_connected({all[0][0]}, {all[1].back()})) {
        reverse(all[0].begin(), all[0].end());
        reverse(all[1].begin(), all[1].end());
        for(auto x : all[1]) all[0].push_back(x);
        return all[0];
    }


    int l0 = 0, r0 = (int)all[0].size() - 1;
    int l1 = 0, r1 = (int)all[1].size() - 1;

    // for(auto& x : all[0]) cout<<x<<' ';
    // cout<<'\n';
    // for(auto& x : all[1]) cout<<x<<' ';
    // cout<<'\n';

    if(are_connected(rng(all[0], l0, r0), rng(all[1], l1, r1)) == 0) {
        if(all[0].size() > all[1].size()) return all[0];
        return all[1];
    }

    while(l0 != r0 || l1 != r1) {
        if(l0 != r0) {
            int m = (l0 + r0) >> 1;
            if(are_connected(rng(all[0], l0, m), rng(all[1], l1, r1))) {
                r0 = m;
            } else {
                l0 = m + 1;
            }
            continue;
        }
        int m = (l1 + r1) >> 1;
        if(are_connected(rng(all[0], l0, r0), rng(all[1], l1, m))) {
            r1 = m;
        } else {
            l1 = m + 1;
        }
    }

    vector<int> res;
    for(int i = 1; i <= all[1].size(); ++i) {
        res.push_back(all[1][(i + l1) % all[1].size()]);
    }
    for(int i = 0; i < all[0].size(); ++i) {
        res.push_back(all[0][(i + l0) % all[0].size()]);
    }
    return res;
}

컴파일 시 표준 에러 (stderr) 메시지

longesttrip.cpp: In function 'std::vector<int> longest_trip(int, int)':
longesttrip.cpp:127:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  127 |     for(int i = 1; i <= all[1].size(); ++i) {
      |                    ~~^~~~~~~~~~~~~~~~
longesttrip.cpp:130:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  130 |     for(int i = 0; i < all[0].size(); ++i) {
      |                    ~~^~~~~~~~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 25 / 25
• Subtask 4: 45 / 60