public class NumContinents {
    public static void main(String[] args) {
        int[][] map = {
            { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
            { 0, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0 },
            { 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 0 },
            { 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0 },
            { 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0 },
            { 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0 },
            { 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0 },
            { 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0 },
            { 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0 },
            { 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0 },
            { 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0 },
            { 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0 },
            { 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 }
        };

        System.out.println(getNumContinents(map));
    }

    public static int getNumContinents(int[][] map) {
        if (map == null) {
            return 0;
        }

        int rows = map.length;

        if (rows == 0) {
            return 0;
        }

        int cols = map[0].length;

        if (cols == 0) {
            return 0;
        }

        boolean[][] visited = new boolean[rows][cols];
        int numContinents = 0;

        for (int row = 0; row < rows; ++row) {
            for (int col = 0; col < cols; ++col) {
                boolean isContinent = traverse(map, visited, row, col);

                if (isContinent) {
                    ++numContinents;
                }
            }
        }

        return numContinents;
    }

    private static boolean traverse(int[][] map, boolean[][] visited, int row, int col) {
        int rows = map.length;
        int cols = map[0].length;

        if (row < 0 || row >= rows || col < 0 || col >= cols || visited[row][col] || map[row][col] == 0) {
            return false;
        }

        visited[row][col] = true;

        traverse(map, visited, row - 1, col);
        traverse(map, visited, row + 1, col);
        traverse(map, visited, row, col + 1);
        traverse(map, visited, row, col - 1);

        return true;
    }
}