Submission #69720

#	Time	Username	Problem	Language	Result	Execution time	Memory
69720		doowey	Cop and Robber (BOI14_coprobber)	C++14	100 / 100	461 ms	10596 KiB

coprobber

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

using namespace std;

#define MAX_N 500

struct Pos{
  int cop_x;
  int robber_x;
  int next_move;
  /* 0 - cop
   * 1 - robber
   */
};

int dp[MAX_N][MAX_N][2];
int nex[MAX_N][MAX_N][2];
int req[MAX_N][MAX_N][2];
int deg[MAX_N];

int go;

int start(int N, bool A[MAX_N][MAX_N]) {
  for(int i = 0;i < N;i ++ ){
    for(int j = 0;j < N; j ++ ){
      deg[i] += A[i][j];
    }
  }
  for(int i = 0;i < MAX_N;i ++ ){
    for(int j = 0;j < MAX_N;j ++ ){
      nex[i][j][0] = -1;
      nex[i][j][1] = -1;
      req[i][j][1] = deg[j];
    }
  }
  queue<Pos> state;
  for(int i = 0;i < N; i ++ ){
    state.push({i, i, 0});
    state.push({i, i, 1});
    dp[i][i][0] = 1;
    dp[i][i][1] = 1;
  }
  Pos cur;
  int cop, robber, nx;
  while(!state.empty()){
    cur = state.front();
    cop = cur.cop_x;
    robber = cur.robber_x;
    nx = cur.next_move;
    state.pop();
    if(nx == 1){
      for(int j = 0; j < N; j ++ ){
        if(A[cop][j] or cop == j){
          if(dp[j][robber][0] == 0){
            dp[j][robber][0] = 1;
            nex[j][robber][0] = cop;
            state.push({j, robber, 0});
          }
        }
      }
    }
    else{
      for(int j = 0;j < N ; j ++ ){
        if(A[robber][j] and robber != j){
          if(dp[cop][j][1] == 0){
            req[cop][j][1] -- ;
            if(req[cop][j][1] == 0){
              dp[cop][j][1] = 1;
              state.push({cop, j, 1});
            }
          }
        }
      }
    }
  }
  bool ok = false;
  go = -1;
  for(int i = 0;i < N ; i ++ ){
    ok = true;
    for(int j = 0;j < N; j ++) {
      if(dp[i][j][0] == 0)
        ok = false;
    }
    if(ok){
      go = i;
      break;
    }
  }
  return go;
  
}

int nextMove(int R) {
  return go = nex[go][R][0];
}

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