https://www.acmicpc.net/problem/2630

색종이 만들기.java

import java.util.*;

public class Main {
    static int[][] field;
    static int white = 0, blue = 0;
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        field = new int[n][n];
        for(int i=0; i<n; i++)
            for(int j=0; j<n; j++)
                field[i][j] = sc.nextInt();
        coleredPaper(n, 0, 0);
        System.out.print(white+"\n"+blue);
        
    }
    static void coleredPaper(int n, int x, int y){
        if(isSame(n, x, y)){
            if (field[y][x] == 0) white++;
            else blue++;
            return;
        }
        coleredPaper(n/2, x, y);
        coleredPaper(n/2, x+n/2, y);
        coleredPaper(n/2, x, y+n/2);
        coleredPaper(n/2, x+n/2, y+n/2);
    }
    static boolean isSame(int n, int x, int y){
        int criteria = field[y][x];
        for(int i=y; i<y+n; i++)
            for(int j=x; j<x+n; j++)
                if (criteria!=field[i][j]) return false;
        return true;
    }
}