제출 #1183848

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1183848		kiwimsy	꿈 (IOI13_dreaming)	C++20	0 / 100	1095 ms	131072 KiB

dreaming

#include "dreaming.h"
#include <bits/stdc++.h>

using namespace std;

vector<vector<pair<int, int>>> adj;
vector<bool> vis, dvis;
vector<int> diapath, diaedges;

void getpath(int a, int b, int N, vector<int> path = {}, vector<int> edges = {}){
    path.push_back(a);
    dvis[a] = true;
    if(a == b){
        diapath = path;
        diaedges = edges;
        return;
    }
    edges.push_back(0);
    for(pair<int, int> i : adj[a]){
        if(!dvis[i.first]){
            edges[edges.size()-1] = i.second;
            getpath(i.first, b, N, path, edges);
        }
    }
}

int diameter(int node, int N){
    diapath.clear(), diaedges.clear();
    int a = 0, b = 0, dist = 0;
    dvis = vis;
    queue<pair<int, int>> q;
    vector<int> dia(N, -1), edges(N), parent(N);
    q.push({node, 0});
    while(!q.empty()){
        pair<int, int> val = q.front();
        q.pop();
        if(dvis[val.first]) continue;
        for(pair<int, int> i : adj[val.first]){
            if(!dvis[i.first]){
                q.push({i.first, i.second + val.second});
                if(i.second + val.second > dist){
                    a = i.first;
                    dist = i.second + val.second;
                }
            }
        }
        dvis[val.first] = true;
    }
    q.push({a, 0});
    dvis = vis, dist = 0;
    dia[0] = a;
    while(!q.empty()){
        pair<int, int> val = q.front();
        q.pop();
        if(dvis[val.first]) continue;
        for(pair<int, int> i : adj[val.first]){
            if(!dvis[i.first]){
                q.push({i.first, i.second + val.second});
                if(i.second + val.second > dist){
                    b = i.first;
                    dist = i.second + val.second;
                }
            }
        }
        dvis[val.first] = true;
    }
    dvis = vis;
    getpath(a, b, N);
    vis = dvis;
    return dist;
}

int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
    adj.resize(N);
    int ret = 0, bigcenter = 0, maxdia = 0;
    vector<int> centers;
    for(int i = 0; i < M; i++){
        adj[A[i]].push_back({B[i], T[i]});
        adj[B[i]].push_back({A[i], T[i]});
    }
    vis.assign(N, false);
    for(int i = 0; i < N; i++){
        if(!vis[i]){
            int dialength = diameter(i, N);
            vis[i] = true;
            int c = i, c1 = i, c2 = i, w1 = 0, w2 = 0;
            if(dialength > 0){
                cerr << "FORWARD:\n";
                for(int j = 0; w1 <= dialength / 2; j++){
                    cerr << w1 << ' ' << dialength/2 << endl;
                    c1 = diapath[j];
                    if(j-1 >= 0) w1 += diaedges[j-1];
                }
                cerr << endl << "BACKWARD:\n";
                for(int j = diapath.size() - 1; w2 <= dialength / 2; j--){
                    cerr << w2 << ' ' << dialength/2 << endl;
                    c2 = diapath[j];
                    if(j < diaedges.size()) w2 += diaedges[j];
                }
                if(w1 > w2) c = c2;
                else c = c1;
                cerr << endl << c1 << ' ' << c2 << endl;
            }
            if(dialength > maxdia){
                bigcenter = c;
                maxdia = dialength;
            }
            centers.push_back(c);
        }
    }
    for(int i : centers){
        cerr << i << ' ';
        if(i != bigcenter){
            adj[i].push_back({bigcenter, L});
            adj[bigcenter].push_back({i, L});
        }
    }
    cerr << endl;
    vis.assign(N, false);
    return diameter(0, N);
}

• Subtask 1: 0 / 14
• Subtask 2: 0 / 10
• Subtask 3: 0 / 23
• Subtask 4: 0 / 18
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23