分享一个C#实现的迷宫生成程序，继续演示LINQ语法在C#中的运用
简单地介绍下这个程序的功能。程序可以自动产生一个迷宫。迷宫的大小可以在
MazeModel mm = new MazeModel(7, 5);
这一行配置。为了简化起见，程序使用控制台输出，稍微修改，可以做到GUI中，效果更好。
迷宫中可以走的路径用|或者-标出，任意两点有且只有一条通路可以到达。大家可以看看自己解迷宫的水平哦。
迷宫算法本质上是一个最小生成树产生算法，这个数据结构大家都学过，忘记的可以自己找出来看看，在本程序中首先建立完整的通路图，然后随机从图中移除一条边，如果移除导致有顶点不可以到达，以后不再尝试移除它，直到图中没有可以移除的边为止。
最后显示输出。
下面是完整的代码，用了一些LINQ来简化搜索边的操作。
using System;using System.Collections.Generic;using System.Diagnostics.Contracts;using System.Linq;using System.Text;namespace ConsoleApplication1{ class Program { static void Main(string[] args) { MazeModel mm = new MazeModel(7, 5); mm.DisplayMaze(); } } class MazeModel { private bool[] edges; public int HorizontalVertex { get; private set; } public int VerticalVertex { get; private set; } private bool getEdgeValue(int edgeindex) { try { return edges[edgeindex]; } catch { return false; } } private void setEdgeValue(int edgeindex, bool value) { try { edges[edgeindex] = value; } catch { } } private int nodeToEdgeIndex(int x, int y, int dir) { if (x == 0 && dir == 1) return -1; if (x % HorizontalVertex == HorizontalVertex - 1 && dir == 2) return -1; if (y == 0 && dir == 0) return -1; if (y >= HorizontalVertex * (VerticalVertex - 1) && dir == 3) return -1; return (y * 2 + ((dir == 1 || dir == 2) ? 0 : (dir == 0 ? -1 : 1))) * HorizontalVertex + x - (dir == 1 ? 1 : 0); } private int nodeindexToEdgeIndex(int nodeindex, int dir) { int x; int y; nodeIndexToNode(nodeindex, out x, out y); return nodeToEdgeIndex(x, y, dir); } private void nodeIndexToNode(int nodeindex, out int x, out int y) { x = nodeindex % HorizontalVertex; y = nodeindex / HorizontalVertex; } private int nodeToNodeIndex(int x, int y) { return y * HorizontalVertex + x; } private void edgeIndexToNodeIndex(int edgeindex, out int node1, out int node2) { int x1 = 0, y1 = 0, x2 = 0, y2 = 0; if (edgeindex / HorizontalVertex % 2 != 0) { x1 = x2 = edgeindex % HorizontalVertex; y1 = edgeindex / (HorizontalVertex * 2); y2 = y1 + 1; } else { x1 = edgeindex % HorizontalVertex; x2 = x1 + 1; y1 = y2 = edgeindex / (HorizontalVertex * 2); } node1 = nodeToNodeIndex(x1, y1); node2 = nodeToNodeIndex(x2, y2); } private int edgeIndexToNodeIndex(int edgeindex, int node) { int node1, node2; edgeIndexToNodeIndex(edgeindex, out node1, out node2); return node1 == node ? node2 : node1; } private IEnumerable<int> getNodeEdges(int nodeIndex, List<int> blocklist) { return Enumerable .Range(0, 4) .Select(x => nodeindexToEdgeIndex(nodeIndex, x)) .Where(x => getEdgeValue(x) && !blocklist.Contains(x)); } private void generateMaze() { List<int> blockEdges = new List<int>(); while (blockEdges.Count < HorizontalVertex * VerticalVertex - 1) { var nodes = Enumerable.Range(0, HorizontalVertex * VerticalVertex) .Where(x => getNodeEdges(x, blockEdges).Count() > 1).ToList() .Select(x => new { k = Guid.NewGuid(), v = x }) .OrderBy(x => x.k) .Select(x => x.v).ToList(); if (nodes.Count == 0) return; int node = nodes.First(); var tedges = getNodeEdges(node, blockEdges).ToList() .Select(x => new { k = Guid.NewGuid(), v = x }) .OrderBy(x => x.k) .Select(x => x.v).ToList(); if (tedges.Count == 0) return; int edge = tedges.First(); var edgesbackup = edges.ToArray(); setEdgeValue(edge, false); if (!testMaze()) { blockEdges.Add(edge); edges = edgesbackup; } } } private bool testMaze() { var found = new List<int>() { 0 }; findNode(0, found); return found.Count() == HorizontalVertex * VerticalVertex; } private void findNode(int nodeindex, List<int> found) { var nextNodes = getNodeEdges(nodeindex, new List<int>()) .Select(x => edgeIndexToNodeIndex(x, nodeindex)) .Where(x => !found.Contains(x)) .ToList(); foreach (int item in nextNodes) { found.Add(item); } foreach (int item in nextNodes) { findNode(item, found); } } public MazeModel(int horizontalvertex, int verticalvertex) { HorizontalVertex = horizontalvertex; VerticalVertex = verticalvertex; edges = Enumerable .Range(0, horizontalvertex * (verticalvertex * 2 - 1) - 1) .Select(x => x % horizontalvertex != horizontalvertex - 1 || x / horizontalvertex % 2 != 0 ).ToArray(); generateMaze(); } public void DisplayMaze() { for (int i = 0; i < VerticalVertex; i++) { for (int j = 0; j < HorizontalVertex; j++) { Console.Write("X"); if (j != HorizontalVertex - 1) { Console.Write(getEdgeValue(nodeToEdgeIndex(j, i, 2)) ? "-" : " "); } } Console.WriteLine(); for (int j = 0; j < HorizontalVertex; j++) { if (i != VerticalVertex - 1) { Console.Write(getEdgeValue(nodeToEdgeIndex(j, i, 3)) ? "|" : " "); Console.Write(" "); } } Console.WriteLine(); } } }}