[Swift] DFS, BFS 메소드

func dfs(_ start: Int) -> [Int] {
    var visitedQueue = [Int]()
    var needVisitedQueue = [start]
    while !needVisitedQueue.isEmpty {
        let node: Int = needVisitedQueue.removeLast()
        if visitedQueue.contains(node) { continue }
        visitedQueue.append(node)
        needVisitedQueue += graph[node].reversed()
    }
    return visitedQueue
}

func bfs(_ start: Int) -> [Int] {
    var visitedQueue = [Int]()
    var needVisitedQueue = [start]
    
    while !needVisitedQueue.isEmpty {
        let node: Int = needVisitedQueue.removeFirst()
        if visitedQueue.contains(node) { continue }
        visitedQueue.append(node)
        needVisitedQueue += graph[node]
    }
    return visitedQueue
}