[백준알고리즘] 2048 (BFS)

작년에 시험장에서 풀었던 건데 그때 왜 못풀었을까...;; 땀땀; 
BFS사용 중복코드 함수로 묶는 법 모름 ~ ;;

import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.LinkedList; import java.util.Queue; import java.util.StringTokenizer; class Map{ int map[][]; int size; public Map(int input_map[][], int size){ this.map=new int[size][size]; this.map=input_map; this.size=size; } } public class Main { static int MAX=-1; public static void main(String[] args) throws IOException{ BufferedReader reader=new BufferedReader(new InputStreamReader(System.in)); StringTokenizer token=new StringTokenizer(reader.readLine()); int n=Integer.parseInt(token.nextToken()); int board[][]=new int [n][n]; for(int i=0;i<n;i++){ token=new StringTokenizer(reader.readLine()); for(int j=0;j<n;j++){ board[i][j]=Integer.parseInt(token.nextToken()); MAX=Math.max(MAX, board[i][j]); } } Map map=new Map(board,n); bfs(map); System.out.println(MAX); } //{up,right,down,left} static int dy[]={1,0,-1,0}; //위로 슬라이드하면 위에서 아래로 돌아야하고 //아래로 슬라이드하면 아래에서 위로 돌아야함 static int dx[]={0,-1,0,1}; public static void bfs(Map board){ Queue<Map> q=new LinkedList<Map>(); q.add(board); int count=0; while(!q.isEmpty()){ count++; int size=q.size(); if(count>5){ break; } while(size-->0){ Map m=q.poll(); for(int i=0;i<4;i++){ int temp[][]=new int[m.size][m.size]; switch(i){ case 0: for(int a=0;a<m.size;a++){ int first_num=0; int second_num=0; int ti=a,tj=0; for(int b=0;b<m.size;b++){ if(m.map[b][a]==0) continue; if(first_num==0){ first_num=m.map[b][a]; }else{ second_num=m.map[b][a]; } temp[tj][ti]=first_num; if(second_num==0){ continue; } if(first_num==second_num){ temp[tj][ti]=first_num+second_num; MAX=Math.max(MAX, first_num+second_num); tj+=dy[i];ti+=dx[i]; first_num=0;second_num=0; }else{ tj+=dy[i];ti+=dx[i]; temp[tj][ti]=second_num; first_num=second_num; second_num=0; } } } Map t1=new Map(temp,m.size); q.add(t1); break; case 1://right for(int a=0;a<m.size;a++){ int first_num=0; int second_num=0; int ti=m.size-1,tj=a; for(int b=m.size-1;b>=0;b--){ if(m.map[a][b]==0) continue; if(first_num==0){ first_num=m.map[a][b]; }else{ second_num=m.map[a][b]; } temp[tj][ti]=first_num; if(second_num==0){ continue; } if(first_num==second_num){ temp[tj][ti]=first_num+second_num; MAX=Math.max(MAX, first_num+second_num); tj+=dy[i];ti+=dx[i]; first_num=0;second_num=0; }else{ tj+=dy[i];ti+=dx[i]; temp[tj][ti]=second_num; first_num=second_num; second_num=0; } } } Map t2=new Map(temp,m.size); q.add(t2); break; case 2: //down for(int a=0;a<m.size;a++){ int first_num=0; int second_num=0; int ti=a,tj=m.size-1; for(int b=m.size-1;b>=0;b--){ if(m.map[b][a]==0) continue; if(first_num==0){ first_num=m.map[b][a]; }else{ second_num=m.map[b][a]; } temp[tj][ti]=first_num; if(second_num==0){ continue; } if(first_num==second_num){ temp[tj][ti]=first_num+second_num; MAX=Math.max(MAX, first_num+second_num); tj+=dy[i];ti+=dx[i]; first_num=0;second_num=0; }else{ tj+=dy[i];ti+=dx[i]; temp[tj][ti]=second_num; first_num=second_num; second_num=0; } } } Map t3=new Map(temp,m.size); q.add(t3); break; case 3: //left for(int a=0;a<m.size;a++){ int first_num=0; int second_num=0; int ti=0,tj=a; for(int b=0;b<m.size;b++){ if(m.map[a][b]==0) continue; if(first_num==0){ first_num=m.map[a][b]; }else{ second_num=m.map[a][b]; } temp[tj][ti]=first_num; if(second_num==0){ continue; } if(first_num==second_num){ temp[tj][ti]=first_num+second_num; MAX=Math.max(MAX, first_num+second_num); tj+=dy[i];ti+=dx[i]; first_num=0;second_num=0; }else{ tj+=dy[i];ti+=dx[i]; temp[tj][ti]=second_num; first_num=second_num; second_num=0; } } } Map t4=new Map(temp,m.size); q.add(t4); break; } } } } } }