public fun connectedComponentsCount() : Int
    {
        var res = 0
        val colors = Array<IntArray>(imgWidth, { IntArray(imgHeight) })

        fun dfs(x : Int, y : Int, color : Int) {
            val dx = array(0, 1, 0, -1)
            var dy = array(1, 0, -1, 0)

            for (i in 0 .. 3) {
                val nx = x + dx[i]
                val ny = y + dy[i]
                if (nx in 0 .. imgWidth - 1 && ny in 0 .. imgHeight - 1 && !bitmap[nx][ny] && colors[nx][ny] == 0) {
                    colors[nx][ny] = color
                    dfs(nx, ny, color)
                }
            }
        }

        for (x in 0 .. imgWidth - 1) {
            for (y in 0 .. imgHeight - 1) {
                if (!bitmap[x][y] && colors[x][y] == 0) {
                    dfs(x, y, ++res)
                }
            }
        }

        return res
    }