Help to Developer

Program to find no.of  connected islands


package example;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class IslandCount {

static int islandCount = 0;

public static void main(String[] args) {

Map<Integer, List<Integer>> map = new HashMap<>();


List<List<Integer>> area = new ArrayList<>();
area.add(Arrays.asList(0, 0, 0, 1, 1, 0, 0));
area.add(Arrays.asList(0, 1, 0, 0, 1, 1, 0));
area.add(Arrays.asList(1, 1, 0, 1, 0, 0, 1));
area.add(Arrays.asList(0, 0, 0, 0, 0, 1, 0));
area.add(Arrays.asList(1, 1, 0, 0, 0, 0, 0));
area.add(Arrays.asList(0, 0, 0, 0, 0, 1, 1));
Integer[][] areaArray = convertListToArray(area);

getBiggestRegion(areaArray);
System.out.println("islandCount :" + islandCount);
}

public static int getRegionSize(Integer[][] matrix, int row, int column) {
if (row < 0 || column < 0 || row >= matrix.length || column >= matrix[row].length) {
return 0;
}
if (matrix[row][column] == 0) {
return 0;
}
//System.out.println(row + " " + column);
matrix[row][column] = 0;
int size = 1;

for (int r = row - 1; r <= row + 1; r++) {
for (int c = column - 1; c <= column + 1; c++) {
if (r != row || c != column) {
// System.out.println(r +" "+ c);
size += getRegionSize(matrix, r, c);
}
}
//System.out.println("*** ");
}
return size;

}

public static int getBiggestRegion(Integer[][] matrix) {

int maxRegion = 0;

for (int row = 0; row < matrix.length; row++) {
for (int column = 0; column < matrix[row].length; column++) {
if (matrix[row][column] == 1) {
int size = getRegionSize(matrix, row, column);
maxRegion = Math.max(size, maxRegion);
islandCount++;
}
}
}
return maxRegion;
}

static Integer[][] convertListToArray(List<List<Integer>> area) {
Integer[][] areaArray = new Integer[area.size()][];
for (int i = 0; i < area.size(); i++) {
List<Integer> list = area.get(i);
System.out.println(list);
areaArray[i] = list.toArray(new Integer[list.size()]);
}
return areaArray;
}

}

output:

[0, 0, 0, 1, 1, 0, 0]
[0, 1, 0, 0, 1, 1, 0]
[1, 1, 0, 1, 0, 0, 1]
[0, 0, 0, 0, 0, 1, 0]
[1, 1, 0, 0, 0, 0, 0]
[0, 0, 0, 0, 0, 1, 1]
islandCount :4