제출 #1024609

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1024609		huutuan	장난감 기차 (IOI17_train)	C++14	27 / 100	841 ms	99592 KiB

train

#include "train.h"

#include <bits/stdc++.h>

using namespace std;

const int N=5010;
vector<int> g[N];
int d[N][N];

void bfs(int root){
   queue<int> q;
   q.push(root);
   while (q.size()){
      int u=q.front();
      q.pop();
      for (int v:g[u]) if (!d[root][v]){
         d[root][v]=1;
         q.push(v);
      }
   }
}

bool bfs2(int root, int n, vector<int> &r){
   if (r[root]) return 0;
   vector<int> dd(n);
   queue<int> q;
   q.push(root);
   while (q.size()){
      int u=q.front();
      q.pop();
      for (int v:g[u]) if (!dd[v] && !r[v]){
         dd[v]=1;
         q.push(v);
      }
   }
   return dd[root];
}

vector<int> va, vb;
int nxt[N];
vector<int> ans, cur, rr;

void backtrackb(int i){
   if (i==(int)vb.size()){
      vector<int> vis(ans.size());
      for (int j=0; j<(int)ans.size(); ++j){
         int u=j;
         while (!vis[u]){
            vis[u]=1;
            u=nxt[u];
         }
         if (vis[u]==1){
            bool cr=0;
            while (vis[u]==1){
               cr|=rr[u];
               vis[u]=2;
               u=nxt[u];
            }
            if (cr){
               while (vis[u]==2){
                  vis[u]=3;
                  u=nxt[u];
               }
            }else{
               while (vis[u]==2){
                  vis[u]=4;
                  u=nxt[u];
               }
            }
         }
         if (vis[u]==4) cur[j]=0;
      }
      return;
   }
   int u=vb[i];
   for (int v:g[u]){
      nxt[u]=v;
      backtrackb(i+1);
   }
}

void backtracka(int i){
   if (i==(int)va.size()){
      cur=vector<int>(ans.size(), 1);
      backtrackb(0);
      for (int j=0; j<(int)ans.size(); ++j) ans[j]|=cur[j];
      return;
   }
   int u=va[i];
   for (int v:g[u]){
      nxt[u]=v;
      backtracka(i+1);
   }
}

vector<int> who_wins(vector<int> a, vector<int> r, vector<int> u, vector<int> v) {
   int n=a.size(), m=u.size();
   bool sub1=1, sub2=1, sub3=1, sub4=1;
   for (int i=0; i<m; ++i) sub1&=u[i]==v[i] || u[i]+1==v[i];
   sub2&=n<=15;
   for (int i:a) sub3&=i, sub4&=!i;
   ans.resize(n, 0);
   rr=r;
   if (sub1){
      vector<int> cyc(n);
      for (int i=0; i<m; ++i) if (u[i]==v[i]) cyc[u[i]]|=1; else cyc[u[i]]|=2;
      for (int i=n-1; i>=0; --i){
         if (cyc[i]==1){
            ans[i]=r[i];
         }else if (cyc[i]==2){
            ans[i]=ans[i+1];
         }else{
            if (a[i]) ans[i]=r[i] || ans[i+1];
            else ans[i]=r[i] && ans[i+1];
         }
      }
      return ans;
   }
   for (int i=0; i<m; ++i) g[u[i]].push_back(v[i]);
   if (sub2){
      for (int i=0; i<n; ++i){
         if (a[i]) va.push_back(i);
         else vb.push_back(i);
      }
      backtracka(0);
      return ans;
   }
   for (int i=0; i<n; ++i) bfs(i);
   if (sub3){
      for (int i=0; i<n; ++i){
         for (int j=0; j<n; ++j) if (r[j]) ans[i]|=d[i][j] && d[j][j];
      }
      return ans;
   }
   if (sub4){
      fill(ans.begin(), ans.end(), 1);
      for (int i=0; i<n; ++i) if (bfs2(i, n, r)){
         for (int j=0; j<n; ++j) if (d[j][i]) ans[j]=0;
      }
      return ans;
   }
   return vector<int>(n, 0);
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 10
• Subtask 3: 11 / 11
• Subtask 4: 11 / 11
• Subtask 5: 0 / 12
• Subtask 6: 0 / 51