133. Clone Graph

main.go

/**
 * Definition for a Node.
 * type Node struct {
 *     Val int
 *     Neighbors []*Node
 * }
 */


func dfs(n *Node, visited map[*Node]*Node) *Node {
    if n == nil {
        return n
    }

    v, ok := visited[n]
    if ok {
        return v
    }

    nn := &Node{Val: n.Val}
    visited[n] = nn

    neighbors := make([]*Node, 0, len(n.Neighbors))
    for _, v := range n.Neighbors {
        neighbors = append(neighbors, dfs(v, visited))
    }
    nn.Neighbors = neighbors
    return nn
}

func cloneGraph(node *Node) *Node {
    visited := make(map[*Node]*Node)
    return dfs(node, visited)
}