[백준] 14891 - 톱니바퀴

14891번: 톱니바퀴

• 코드

  package review;
  
  import java.io.BufferedReader;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.ArrayDeque;
  import java.util.Deque;
  import java.util.StringTokenizer;
  
  public class ex_14891 {
      static Deque<Integer>[] dq;
      static int [] sum ={1,2,4,8};
      static int [] turnArr;
      public static void main(String[] args) throws IOException {
          System.setIn(new FileInputStream("input/14891.txt"));
          BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
          dq = new ArrayDeque[5];
  
          for(int i=1;i<=4;i++){
              String now = br.readLine();
              dq[i]=new ArrayDeque<>();
              for(int j=0;j<8;j++){
                  dq[i].addLast(Integer.parseInt(now.substring(j,j+1)));
              }
          }
          int K = Integer.parseInt(br.readLine());
          for(int i=0;i<K;i++){
              StringTokenizer st = new StringTokenizer(br.readLine());
              int num = Integer.parseInt(st.nextToken());
              int dir = Integer.parseInt(st.nextToken());
              boolean flag=false;
              turnArr=new int[5];
              turnArr[num]=dir;
  
              switch(num){
                  case 1:
                      flag = cycle(1,2,2,dir);
                      if(flag) flag = cycle(2,3,3,-dir);
                      if(flag) cycle(3,4,4,dir);
                      break;
                  case 2:
                      cycle(1,2,1,dir);
                      flag = cycle(2,3,3,dir);
                      if(flag) cycle(3,4,4,-dir);
                      break;
                  case 3:
                      flag = cycle(2,3,2,dir);
                      if(flag) flag = cycle(1,2,1,-dir);
                      cycle(3,4,4,dir);
                      break;
                  case 4:
                      flag = cycle(3,4,3,dir);
                      if(flag) flag = cycle(2,3,2,-dir);
                      if(flag) cycle(1,2,1, dir);
                      break;
              }
              for(int j=1;j<=4;j++){
                  if(turnArr[j]!=0){
                      turn(j,turnArr[j]);
                  }
              }
          }
          System.out.println(count());
      }static void turn(int index, int dir){
          if(dir==1){
              int now = dq[index].pollLast();
              dq[index].addFirst(now);
          }else{
              int now = dq[index].pollFirst();
              dq[index].addLast(now);
          }
      }static int getThird(int index){
          int first=dq[index].pollFirst();
          int second=dq[index].pollFirst();
          int third=dq[index].getFirst();
          dq[index].addFirst(second);
          dq[index].addFirst(first);
          return third;
      }static int getSix(int index){
          int first=dq[index].pollLast();
          int second=dq[index].getLast();
          dq[index].addLast(first);
          return second;
      }static boolean cycle(int x, int y, int next, int dir){
          int one = getThird(x);
          int two = getSix(y);
          if(one!=two) {
              turnArr[next]=-dir;
              return true;
          }
          return false;
      }static int count(){
          int answer=0;
          for(int i=1;i<=4;i++){
              if(dq[i].getFirst()==1) answer+=sum[i-1];
          }
          return answer;
      }
  }

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