package DynamicProgramming;

import java.util.ArrayList;

public class IsLand {

public static void main(String[] args) {

ArrayList<String> visited = new ArrayList<>();

Character[][] island = {

{ 'W', 'L', 'L', 'W' },

{ 'W', 'L', 'W', 'W' },

{ 'W', 'W', 'W', 'W' },

{ 'W', 'W', 'L', 'W' }

};

int landCount = 0, row = island.length, col = island[0].length;

for (int i = 0; i < row; i++) {

for (int j = 0; j < col; j++) {

if (exploreIsLand(island, i, j, visited))

landCount += 1;

}

}

System.out.println("Number of IsLand: " + landCount);

}

static boolean exploreIsLand(Character[][] island, int row, int col, ArrayList<String> visited) {

String key = row + "," + col;

boolean rowBound = row >= 0 && row < island.length;

boolean colBound = col >= 0 && col < island[0].length;

if (!rowBound || !colBound)

return false;

if (visited.contains(key)) {

return false;

}

visited.add(key);

if (island[row][col] == 'W')

return false;

exploreIsLand(island, row + 1, col, visited);

exploreIsLand(island, row - 1, col, visited);

exploreIsLand(island, row, col + 1, visited);

exploreIsLand(island, row, col - 1, visited);

return true;

}

}