最长路径我有一个问题,我的解决方案,在图中寻找最长路径。当顶点彼此靠近时,我的程序工作非常缓慢。这里是我的代码,请帮助我。如何找到在图形
测试类
public class GraphTest : MonoBehaviour {
// Use this for initialization
void Start() {
const int w = 5;
const int h = 4;
int[,] data = new int[h,w]{
{0,0,0,1,0},
{0,0,0,1,0},
{0,0,1,1,0},
{0,0,0,0,0}};
Map map = new Map(data,w,h);
List<Node> longest = map.longestPath();
Debug.Log("LONGEST " + longest.Count);
//INFO this doing for printing array with steps
int c = longest.Count-1;
foreach(Node n in longest)
data[n.r,n.c] = c--;
string st = "";
for(int i = 0; i < h; i++)
{
for(int j = 0; j < w; j++)
{
st += data[i,j] + ",";
}
st += "\n";
}
Debug.Log(st);
}
}
Node类
public class Node
{
public int r,c;
public int data;
public Node[] neighbors;
public Node(int r, int c, int data)
{
this.r = r;
this.c = c;
this.data = data;
neighbors = new Node[8];
}
}
地图类查找路径
public class Map
{
public static int[] xDir = {1,1,1,0,-1,-1,-1,0};
public static int[] yDir = {-1,0,1,1,1,0,-1,-1};
public Node[,] map;
public int[,] mapData;
private int width,height;
private int[,] marks;
public Map(int[,] mapData,int width,int height)
{
this.mapData = mapData;
this.width = width;
this.height = height;
createNodes();
initNeighbors();
}
//INFO create nodes
private void createNodes()
{
map = new Node[height,width];
for(int i = 0; i < height; i++)
{
for(int j = 0; j < width; j++)
{
map[i,j] = new Node(i,j,mapData[i,j]);
}
}
}
//INFO assign neighbor nodes
private void initNeighbors()
{
for(int i = 0; i < height; i++)
{
for(int j = 0; j < width; j++)
{
for(int k = 0; k < 8; k++)
{
if(inRange(i+yDir[k],j+xDir[k]))
{
map[i,j].neighbors[k] = map[i+yDir[k],j+xDir[k]];
}
}
}
}
}
private bool inRange(int r, int c)
{
return r < height && r >= 0 && c < width && c >= 0;
}
public List<Node> longestPath()
{
marks = new int[height,width];
List<Node> nodes = new List<Node>();
int c = dfs(map[0,0],nodes);
//INFO Iterasions count
Debug.Log("COUNT " + c);
return nodes;
}
private int dfs(Node node, List<Node> nodes)
{
int i = 1;
List<Node> longest = new List<Node>();
List<Node> list = null;
marks[node.r,node.c] = 1;
for(int n = 0; n < 8; n++)
{
//INFO if the neighbor node is not null and same type with parent node do dfs for neighbor node
if(node.neighbors[n] != null &&
marks[node.neighbors[n].r,node.neighbors[n].c] == 0 &&
node.neighbors[n].data == node.data)
{
list = new List<Node>();
i += dfs(node.neighbors[n],list);
//INFO if the found nodes count is more than previous nodes count set new nodes to best nodes
if(list.Count > longest.Count)
longest = list;
}
}
marks[node.r,node.c] = 0;
longest.Add(node);
nodes.AddRange(longest);
return i;
}
}
我很好奇你正在尝试做什么?你能否详细说明一下。这是为了一场比赛吗? – Postlagerkarte 2014-09-22 09:35:14