가장 큰 정사각형 찾기 (연습문제)

원본 : https://school.programmers.co.kr/learn/courses/30/lessons/12905

프로그래머스

 

풀이

class Solution
{
    public int solution(int [][]board)
    {
        for (int i = 1; i < board.length; i++) {
            for (int j = 1; j < board[0].length; j++) {
                if (board[i][j] != 0) {
                    board[i][j] = getValue(board, i, j);
                }
            }
        }

        int maxValue = 0;

        for (int[] boardRow : board) {
            for (int j = 0; j < board[0].length; j++) {
                maxValue = Math.max(maxValue, boardRow[j]);
            }
        }

        return maxValue * maxValue;
    }

    public int getValue(int[][] arr, int i, int j) {
        return Math.min(arr[i - 1][j - 1], Math.min(arr[i - 1][j], arr[i][j - 1])) + 1;
    }
}