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我曾尝试在 c# 中实现深度优先搜索，但我不确定如何以分布式计算方式执行此操作。如果你们能在这方面帮助我，我将非常感激:) 你可以在下面找到我的 DFS 代码

public class DFS
{ 
static List<string> traversedList = new List<string>();
static List<string> parentList = new List<string>();

public static void Main(string[] args)
{

    int N = 100;
    int M = N * 4;
    int P = N * 16;

    Stack newstack = new Stack();

    List<string> global_list=new List<string>();

    StreamReader file = new StreamReader("my input file");

    string text = file.ReadToEnd();

    string[] lines = text.Split('\n');

    string[][] array1 = new string[lines.Length][];

    for (int i = 0; i < lines.Length; i++)
    {
        lines[i] = lines[i].Trim();
        string[] words = lines[i].Split(' ');

        array1[i] = new string[words.Length];

        for (int j = 0; j < words.Length; j++)
        {
            array1[i][j] = words[j];
        }
    }

    StreamWriter sr = new StreamWriter(args[0]);

    for (int i = 0; i < array1.Length; i++)
    {
        for (int j = 0; j < array1[i].Length; j++)
        {
            if (j != 0 )
            {
                sr.Write(array1[i][0] + ":" + array1[i][j]);
                Console.WriteLine(array1[i][0] + ":" + array1[i][j]);
                sr.Write(sr.NewLine);
            }
        }

    }

    int start_no = Convert.ToInt32(args[args.Length-1]);

    traversedList.Add(start_no.ToString());
    parentList.Add("root");
    dfs(array1, start_no);

    for (int z = 0; z < traversedList.Count; z++)
    {
            Console.WriteLine(traversedList.ElementAt(z) + " "+parentList.ElementAt(z)+" "+(z+1));
     }
    Console.ReadLine();
}

private static void dfs(string[][] array, int point)
{
    for (int z = 1; z < array[point].Length; z++)
        {
            if ((!traversedList.Contains(array[point][z])))
            {
                traversedList.Add(array[point][z]);
                parentList.Add(point.ToString());
                dfs(array, int.Parse(array[point][z]));
            }
        }
        return;
}

}

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1 回答 1

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你应该从计算机国际象棋（现在演变成世界冠军计算机游戏玩家）的世界中阅读文献。他们已经进行分布式深度优先搜索大约 30 年了，并且有很多想法。正确处理很棘手，因为您必须在不知道特定分支可能包含多少工作的情况下平均分配工作。

看看Monty Newborn或麦吉尔大学，这在大约 10 年前似乎是这方面的温床。

And of course, GIYF: "distributed depth first search" produced a reference to this paper: Distributed Algorithms for Depth-First Search. I'd guess it contains lots of ideas from the computer chess world.

The problems for *shared memory" DFS a bit less difficult; you don't have to send messages to your distributed helpers, you can simply pass a pointer :-} It helps to have a language which provides you with parallelism and manages explosive parallelism growth that can occur if your program forks on every branch. I offer an example 4x4 N-puzzle solver built in a parallel programming language I designed. (This example was one of my earliest SO posts!).

于 2012-06-02T02:28:20.200 回答