제출 #1014370

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1014370		JakobZorz	가장 긴 여행 (IOI23_longesttrip)	C++17	70 / 100	21 ms	1132 KiB

longesttrip

#include"longesttrip.h"
#include<iostream>
#include<algorithm>
using namespace std;

int n;

pair<int,int>find_conn(vector<int>v1,vector<int>v2){
    for(int i:v1){
        if(are_connected({i},v2)){
            for(int j:v2){
                if(are_connected({i},{j}))
                    return{i,j};
            }
        }
    }
    // impossible
    exit(1);
}

vector<int>merge(vector<int>v1,vector<int>v2){
    while(v2.size()){
        v1.push_back(v2.back());
        v2.pop_back();
    }
    return v1;
}

pair<vector<int>,vector<int>>merge(vector<int>v1,vector<int>v2,vector<int>v3){
    if(are_connected({v1.back()},{v2.back()}))
        return{merge(v1,v2),v3};
    
    if(are_connected({v2.back()},{v3.back()}))
        return{merge(v2,v3),v1};
    
    return{merge(v1,v3),v2};
}

vector<int>cyclic_shift(vector<int>arr,int a){
    // it ends with a
    vector<int>res;
    bool b1=false;
    for(int i:arr){
        if(b1)
            res.push_back(i);
        if(i==a)
            b1=true;
    }
    
    bool b2=true;
    for(int i:arr){
        if(b2)
            res.push_back(i);
        if(i==a)
            b2=false;
    }
    return res;
}

vector<int>longest_trip(int N,int D){
    n=N;
    vector<vector<int>>arr;
    for(int i=0;i<n;i++)
        arr.push_back({i});
    
    while(arr.size()>2){
        vector<int>v1,v2,v3;
        v1=arr.back();
        arr.pop_back();
        v2=arr.back();
        arr.pop_back();
        v3=arr.back();
        arr.pop_back();
        auto res=merge(v1,v2,v3);
        arr.push_back(res.first);
        arr.push_back(res.second);
    }
    
    vector<int>res1=arr[0];
    vector<int>res2=arr[1];
    
    if(!are_connected(res1,res2)){
        if(res1.size()>res2.size())
            return res1;
        else
            return res2;
    }
    
    if(are_connected({res1.back()},{res2.back()}))
        return merge(res1,res2);
    reverse(res1.begin(),res1.end());
    if(are_connected({res1.back()},{res2.back()}))
        return merge(res1,res2);
    reverse(res2.begin(),res2.end());
    if(are_connected({res1.back()},{res2.back()}))
        return merge(res1,res2);
    reverse(res1.begin(),res1.end());
    if(are_connected({res1.back()},{res2.back()}))
        return merge(res1,res2);
    
    // both must be cyclical then
    auto pr=find_conn(res1,res2);
    vector<int>r1=cyclic_shift(res1,pr.first);
    vector<int>r2=cyclic_shift(res2,pr.second);
    return merge(r1,r2);
}

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 25 / 25
• Subtask 4: 30 / 60