var maxConnectedCells: Int = 0
var connectedCells: Int = 0
var grid: [[Cell]] = []
var visited: [Cell] = []
 
class Cell {
    var filled: Bool = false
    var i: Int = 0
    var j: Int = 0
}

func connectedCell(matrix: [[Int]]) -> Int {
    createCells(matrix: matrix)

    for row in grid {

        connectedCells = 0

    innerLoop: for cell in row {
            if !cell.filled { break innerLoop }
            if cell.filled && !visited.contains(where: { $0.i == cell.i && $0.j == cell.j }) {
                markCurrentCell(cell: cell)
            }
        }
    }

    return maxConnectedCells
}

private func markCurrentCell(cell: Cell) {
    visited.append(cell)
    connectedCells += 1
    let largest = max(maxConnectedCells, connectedCells)
    maxConnectedCells = largest

    exploreAround(i: cell.i, j: cell.j)
}

private func exploreAround(i: Int, j: Int) {
    let directions = [(-1, -1), (0, -1), (-1, 1), (1, 1), (0, 1), (-1, 0), (1, -1), (1, 0)]

    for direction in directions {
        let newI = i + direction.0
        let newJ = j + direction.1

        if (newI < 0) || (newI >= grid.count) {
            continue
        }

        if (newJ < 0) || (newJ >= grid[newI].count) {
            continue
        }

        let cell = grid[newI][newJ]

        guard cell.filled && !visited.contains(where: { $0.i == cell.i && $0.j == cell.j }) else {
            continue
        }

        visited.append(cell)
        connectedCells += 1
        let largest = max(maxConnectedCells, connectedCells)
        maxConnectedCells = largest

        exploreMore(cell: cell)
    }
}

private func exploreMore(cell: Cell) {
    let directions = [(-1, -1), (0, -1), (-1, 1), (1, 1), (0, 1), (-1, 0), (1, -1), (1, 0)]

    for direction in directions {
        let newI = cell.i + direction.0
        let newJ = cell.j + direction.1

        if (newI < 0) || (newI >= grid.count) {
            continue
        }

        if (newJ < 0) || (newJ >= grid[newI].count) {
            continue
        }

        let cell = grid[newI][newJ]

        guard cell.filled && !visited.contains(where: { $0.i == cell.i && $0.j == cell.j }) else {
            continue
        }

        visited.append(cell)
        connectedCells += 1
        let largest = max(maxConnectedCells, connectedCells)
        maxConnectedCells = largest
    
        exploreMore(cell: cell)
    }
}

private func createCells(matrix: [[Int]]) {
    var collumns: [[Cell]] = []
    for (i, _) in matrix.enumerated() {
        var row: [Cell] = []
        for (j, _) in matrix[i].enumerated() {
            let cell = Cell()
            cell.filled = matrix[i][j] == 1 ? true : false
            cell.i = i
            cell.j = j
            row.append(cell)
        }
        collumns.append(row)
    }
    grid = collumns
}