Submission #521228

#	Time	Username	Problem	Language	Result	Execution time	Memory
521228		79brue	Park (JOI17_park)	C++14	100 / 100	581 ms	1988 KiB

park

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

using namespace std;

typedef long long ll;

int n;
int query_arr[2002];

bool visited[2002];
int par[2002];
int depth[2002];
bool inRecursion[2002];

void query_select(vector<int>& v){
    for(int i=0; i<n; i++) query_arr[i] = 0;
    for(auto x: v) query_arr[x] = 1;
}

void solve(int x){
    inRecursion[x] = 1;
    /// 현재 방문한 곳만으로 접근 가능한지 판별
    for(int i=0; i<n; i++){
        query_arr[i] = visited[i];
    }
    query_arr[x] = 1;
    if(Ask(0, x, query_arr)){ /// 접근 가능
        vector<int> vec;
        for(int i=0; i<n; i++) if(visited[i]) vec.push_back(i);
        sort(vec.begin(), vec.end(), [&](int a, int b){
            return depth[a] < depth[b];
        });

        int l = 0, r = (int)vec.size()-1;
        while(l<r){
            int m = (l+r)>>1;

            memset(query_arr, 0, sizeof(query_arr));
            vector<int> checklist;
            for(int i=l; i<=m; i++){
                checklist.push_back(vec[i]);
                query_arr[vec[i]] = 1;
            }
            for(int i=0; i<(int)checklist.size(); i++){
                if(checklist[i] && !query_arr[par[checklist[i]]]){
                    checklist.push_back(par[checklist[i]]);
                    query_arr[par[checklist[i]]] = 1;
                }
            }

            query_arr[x] = 1;
            bool ret = Ask(0, x, query_arr);
            for(auto v: checklist) query_arr[v] = 0;

            if(ret) r = m;
            else l = m+1;
        }

        par[x] = vec[l];
        Answer(min(par[x], x), max(par[x], x));

        visited[x] = 1;
        depth[x] = depth[par[x]] + 1;
    }
    else{
        vector<int> vec;
        for(int i=0; i<n; i++) if(!inRecursion[i] && x!=i) vec.push_back(i);

        int l = 0, r = (int)vec.size()-1, qa = (int)vec.size() - 1;
        while(l<=r){
            int m = (l+r)>>1;
            for(int i=0; i<=m; i++){
                query_arr[vec[i]] = 1;
            }
            bool ret = Ask(0, x, query_arr);
            for(int i=0; i<=m; i++){
                query_arr[vec[i]] = 0;
            }

            if(ret){ /// 접근 가능 -> 줄여야 함
                qa = m;
                r = m-1;
            }
            else{
                l = m+1;
            }
        }
        solve(vec[qa]);
        solve(x);
    }
}

int deg[2002];
vector<int> link[2002];
bool chk[2002][2002];

void dfs_insert(int x, int p, vector<int>& v){
    v.push_back(x);
    for(auto y: link[x]){
        if(p==y) continue;
        dfs_insert(y, x, v);
    }
}

void reorder(int x, int p = -1){
    par[x] = p;
    for(auto y: link[x]){
        if(p==y) continue;
        depth[y] = depth[x] + 1;
        reorder(y, x);
    }
}

void solve_cross(int o, int x, int p){ /// o - ... - p - x
    if(deg[o] == 7) return;

    vector<int> vec;
    dfs_insert(x, p, vec);

    int basel, l, r, qa;
    vector<int> checklist;

    retry:

    if(vec.empty()) return;
    memset(query_arr, 0, sizeof(query_arr));
    query_arr[o] = query_arr[x] = 1;
    checklist.clear();

    for(auto x: vec){
        checklist.push_back(x);
        query_arr[x] = 1;
    }
    for(int i=0; i<(int)checklist.size(); i++){
        if(par[checklist[i]] != p && !query_arr[par[checklist[i]]]){
            query_arr[par[checklist[i]]] = 1;
            checklist.push_back(par[checklist[i]]);
        }
    }

    if(!Ask(min(o, x), max(o, x), query_arr)) return;

    l = 0, r = (int)vec.size()-1, qa = (int)vec.size() - 1;
    while(l<=r){
        int m = (l+r)>>1;
        memset(query_arr, 0, sizeof(query_arr));
        query_arr[x] = query_arr[o] = 1;

        checklist.clear();
        for(int i=l; i<=m; i++){
            checklist.push_back(vec[i]);
            query_arr[vec[i]] = 1;
        }
        for(int i=0; i<(int)checklist.size(); i++){
            if(par[checklist[i]] != p && !query_arr[par[checklist[i]]]){
                query_arr[par[checklist[i]]] = 1;
                checklist.push_back(par[checklist[i]]);
            }
        }

        if(Ask(min(o, x), max(o, x), query_arr)){
            qa = m;
            r = m-1;
        }
        else l = m+1;
    }

    if(!chk[min(o, vec[qa])][max(o, vec[qa])]){
        deg[o]++, deg[vec[qa]]++;
        chk[min(o, vec[qa])][max(o, vec[qa])] = 1;
        Answer(min(o, vec[qa]), max(o, vec[qa]));
    }

    for(auto nxt: link[vec[qa]]){
        if(nxt == par[vec[qa]]) continue;
        solve_cross(o, nxt, vec[qa]);
    }

    basel = qa+1;
    while(basel < (int)vec.size() && depth[vec[basel]] > depth[vec[qa]]) basel++;
    if(basel == (int)vec.size()) return;

    vec.erase(vec.begin(), vec.begin() + basel);
    goto retry;
}

void Detect(int t, int N){
    n = N;

    visited[0] = 1;
    for(int i=1; i<n; i++){
        if(visited[i]) continue;
        solve(i);
    }

    for(int i=1; i<n; i++){
        deg[i]++, deg[par[i]]++;
        link[par[i]].push_back(i), link[i].push_back(par[i]);
    }

    for(int i=0; i<n; i++){
        depth[i] = 0;
        reorder(i);
//        if(i==49){
//            puts("");
//        }
        for(auto j: link[i]){
            for(auto k: link[j]){
                if(k==i) continue;
                solve_cross(i, k, j);
            }
        }
    }
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 27 / 27
• Subtask 4: 30 / 30
• Subtask 5: 23 / 23