Submission #1155455

#	Time	Username	Problem	Language	Result	Execution time	Memory
1155455		Ludissey	Cop and Robber (BOI14_coprobber)	C++20	100 / 100	547 ms	21544 KiB

coprobber

#include "coprobber.h"
#include <bits/stdc++.h>
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
 
using namespace std;

vector<vector<int>> neigh;
vector<vector<vector<int>>> visited;
vector<vector<int>> nxt;
int pos=0;
int start(int N, bool A[MAX_N][MAX_N])
{
    visited.resize(N,vector<vector<int>>(N,vector<int>(2,0)));
    neigh.resize(N);
    nxt.resize(N,vector<int>(N,0));
    for (int i = 0; i < N; i++)
    {
        for (int j = i+1; j < N; j++)
        {
            if(A[i][j]) { neigh[i].push_back(j); neigh[j].push_back(i); }
        }
    }
    queue<pair<pair<int,int>,bool>> queue;
    vector<vector<int>> cnt(N,vector<int>(N,0));
    for (int i = 0; i < N; i++) {
        queue.push({{i,i},true});
        queue.push({{i,i},false});
    }
    while(!queue.empty()){
        int p=queue.front().first.first;
        int b=queue.front().first.second;
        int t=queue.front().second;
        queue.pop();
        if(visited[p][b][t]==2) continue;
        visited[p][b][t]=2;
        if(!t){
            for (auto u : neigh[b])
            {
                cnt[p][u]++;
                if(cnt[p][u]==sz(neigh[u])) {
                    if(visited[p][u][1]==0){
                        queue.push({{p,u},true});
                        visited[p][u][1]=1;
                    }
                }
            }
        }else{
            for (auto u : neigh[p])
            {
                if(visited[u][b][false]==0) {
                    nxt[u][b]=p;
                    queue.push({{u,b},false});
                    visited[u][b][0]=1;
                }
            }
            if(visited[p][b][false]==0) {
                nxt[p][b]=p;
                queue.push({{p,b},false});
                visited[p][b][0]=1;
            }
        }
    }
    for (int i = 0; i < N; i++)
    {
        bool b=true;
        for (int j = 0; j < N; j++)
        {
            if(!visited[i][j][1]) b=false;
        }
        if(b){
            pos=i;
            return i;
        }
    }
    return -1;
}

int nextMove(int R)
{
    return pos=nxt[pos][R];
}

• Subtask 1: 16 / 16
• Subtask 2: 14 / 14
• Subtask 3: 30 / 30
• Subtask 4: 40 / 40