package LeetCode;

import java.util.ArrayDeque;
import java.util.Deque;

public class LC_695 {

    static Deque<int[]> deque = new ArrayDeque<>();
    static int[][] move = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
    static int max = 0;

    public static void main(String[] args) {
        int[][] grid = {
                {0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0},
                {0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0},
                {0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0},
                {0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0},
                {0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0},
                {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0},
                {0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0},
                {0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0}
        };
        System.out.println(maxAreaOfIsland(grid));
    }

    public static int maxAreaOfIsland(int[][] grid) {
        boolean[][] visited = new boolean[grid.length][grid[0].length];
        for (int i = 0; i < grid.length; i++) {
            for (int j = 0; j < grid[0].length; j++) {
                if (grid[i][j] == 1 && !visited[i][j]) {
                    deque.offer(new int[]{i, j});
                    visited[i][j] = true;
                    bfs(grid,visited);
                }
            }
        }
        return max;
    }

    public static void bfs(int[][] grid,boolean[][] visited) {
        int cont = 1;
        while (!deque.isEmpty()) {
            int x = deque.getFirst()[0];
            int y = deque.getFirst()[1];
            deque.removeFirst();
            for (int i = 0; i < move.length; i++) {
                int nextx = x + move[i][0];
                int nexty = y + move[i][1];
                if (nextx < 0 || nextx > grid.length - 1 || nexty < 0 || nexty > grid[0].length - 1) continue;
                else {
                    if (grid[nextx][nexty] == 1 && !visited[nextx][nexty]) {
                        cont++;
                        deque.add(new int[]{nextx, nexty});
                        visited[nextx][nexty] = true;
                    }
                }
            }
            max = Math.max(cont, max);
        }
    }
}