더블릿, 자리배정 문제 알고리즘(http://59.23.113.171/pool/koi_seat/koi_seat.php?pname=koi_seat)

Koi_Seat.java

import java.util.Scanner;

public class Koi_Seat {

    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);
        int y = in.nextInt();
        int x = in.nextInt();
        int targetNumber = in.nextInt();
        in.close();
        
//        int y = 5;
//        int x = 180;
//        int targetNumber = 899;
        
        int[][] array = new int[x][y];
        int round = 0;
        int prevNumber = 1;

        while (true) {

            int number = (x * 2 + (y - 2) * 2) + prevNumber;

            if (prevNumber <= targetNumber && targetNumber < number) {
                check(array, round, targetNumber, prevNumber);
                break;
            } else if (prevNumber == targetNumber && targetNumber == number) {
                check(array, round, targetNumber, prevNumber);
                break;
            }

            prevNumber = number;
            round++;
            x -= 2;
            y -= 2;
            
            if (x <= 0 || y <= 0) {
                round = -1;
                break;
            }
                
        }

        if(round == -1)
            System.out.println("0");
        
//        check(array, 3, x, y, 11, 43);
        
//        for (int[] ys : array) {
//            for (int yt : ys)
//                System.out.printf("%3d ", yt);
//            System.out.println();
//        }
    }

    public static void check(int[][] array, int round, int number, int countNumber) {

        int x = array.length;
        int y = array[0].length;
        
        int count = countNumber;
        int startX = round;
        int startY = round;

        // x 증가
        for (; startX < x-round; startX++) {

            array[startX][startY] = count++;

            if (array[startX][startY] == number) {
                print(startX, startY);
                return;
            }
        }

        startX--;
        startY++;

        // y 증가
        for (; startY < y-round; startY++) {

            array[startX][startY] = count++;

            if (array[startX][startY] == number) {
                print(startX, startY);
                return;
            }
        }

        startX--;
        startY--;

        // x 감소
        for (; startX > round; startX--) {

            array[startX][startY] = count++;

            if (array[startX][startY] == number) {
                print(startX, startY);
                return;
            }
        }

        // y 감소
        for (; startY > round; startY--) {

            array[startX][startY] = count++;

            if (array[startX][startY] == number) {
                print(startX, startY);
                return;
            }
        }
    }

    public static void print(int x, int y) {
        System.out.printf("%d %d\n", y+1, x+1);
    }
}