using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConAppDijkstra
{
class Program
{
private const int MaxSize = 6;
private const int INF = 32767; //INF表示∞
private const int MAXV = 4; //最大顶点个数
//结构体的成员定义里不能直接赋值，也就是等号后的应该移除，在你后面实例化整个结构体以后，
//再对Study_Data[n].input=new double[50] 其他成员类似。顺便说下其实用class简单得多。
struct VertexType
{
public string VexNo; //顶点编号
public string VexName; //顶点名称
public string otherInfo; //顶点其他信息
} ; //顶点类型
struct MGraph //图的定义
{
public int[,] edges; //邻接矩阵
public int n, e; //顶点数,弧数
public VertexType[] vexs; //存放顶点信息
} ; //图的邻接矩阵类型
static void Ppath(int[] path, int i, int v) //前向递归查找路径上的顶点
{
int k;
k = path[i];
if (k == v) return; //找到了起点则返回
Ppath(path, k, v); //找顶点k的前一个顶点v
Console.Write("{0},", k); //输出路径上的终点
// Ppath(path, k, j); //找顶点k的前一个顶点j
}
static void Ppath(MGraph g,int[] path, int i, int v) //前向递归查找路径上的顶点
{
int k;
k = path[i];
if (k == v) return; //找到了起点则返回
Ppath(path, k, v); //找顶点k的前一个顶点v
Console.Write("{0},", g.vexs[k].VexName); //输出路径上的终点
// Ppath(path, k, j); //找顶点k的前一个顶点j
}
static void Dispath(int[] dist, int[] path, int[] s, int n, int v)
{
int i;
for (i = 0; i < n; i++)
{
if (s[i] == 1)
{
Console.Write(" 从{0}到{1}的最短路径长度为:{2}\t路径为:", v, i, dist[i]);
Console.Write("{0},", v); //输出路径上的起点
Ppath(path, i, v); //输出路径上的中间点
Console.WriteLine("{0}", i); //输出路径上的终点
}
else
Console.WriteLine("从{0}到{1}不存在路径\n", v, i);
}
}
static void PutBothpath(MGraph g, int[] dist, int[] path, int[] s, int n, int v, int m)
{
int i;
for (i = 0; i < n; i++)
{
if (s[i] == 1)
{
//Console.Write(" 从{0}到{1}的最短路径长度为:{2}\t路径为:", v, i, dist[i]);
//Console.Write("{0},", v); //输出路径上的起点
//Ppath(path, i, v); //输出路径上的中间点
//Console.WriteLine("{0}", i); //输出路径上的终点
if (i == m && dist[i] < INF)
{
Console.Write(" 从{0}到{1}的最短路径长度为:{2}\t路径为:", g.vexs[v].VexName, g.vexs[i].VexName, dist[i]);
Console.Write("{0},", g.vexs[v].VexName); //输出路径上的起点
//Ppath(path, i, v); //输出路径上的中间点
Ppath(g, path, i, v);
Console.WriteLine("{0}", g.vexs[i].VexName); //输出路径上的终点
}
}
else
Console.WriteLine("从{0}到{1}不存在路径\n", v, i);
}
}
static void Dijkstra(MGraph g, int v)
{
int[] dist = new int[MAXV];//从原点v到其他的各定点当前的最短路径长度
int[] path = new int[MAXV];//path[i]表示从原点到定点i之间最短路径的前驱节点
int[] s = new int[MAXV]; //选定的顶点的集合
int mindis, i, j, u;
u = 0;
for (i = 0; i < g.n; i++)
{
dist[i] = g.edges[v, i]; //距离初始化
s[i] = 0; //s[]置空 0表示i不在s集合中
if (g.edges[v, i] < INF) //路径初始化
path[i] = v;
else
path[i] = -1;
}
s[v] = 1; //源点编号v放入s中
path[v] = 0;
for (i = 0; i < g.n; i++) //循环直到所有顶点的最短路径都求出
{
mindis = INF; //mindis置最小长度初值
for (j = 0; j < g.n; j++) //选取不在s中且具有最小距离的顶点u
if (s[j] == 0 && dist[j] < mindis)
{
u = j;
mindis = dist[j];
}
s[u] = 1; //顶点u加入s中
for (j = 0; j < g.n; j++) //修改不在s中的顶点的距离
if (s[j] == 0)
if (g.edges[u, j] < INF && dist[u] + g.edges[u, j] < dist[j])
{
dist[j] = dist[u] + g.edges[u, j];
path[j] = u;
}
}
Dispath(dist, path, s, g.n, v); //输出最短路径
//PutBothpath(g, dist, path, s, g.n, v, 3);
}
static void initdata()
{
int i, j;
MGraph g;
g.n = 4; g.e = 8;
g.edges = new int[MAXV, MAXV];
g.vexs = new VertexType[MAXV];
//int [,] anArray = new int [2, 4] {{1,2,3,4},{5,6,7,8}};
int[,] a = new int[MAXV, MAXV] {
{0, 5,INF,7},
{INF,0, 4,2},
{3, 3, 0,2},
{INF,INF,1,0}
};
for (i = 0; i < g.n; i++) //建立图的图的邻接矩阵
{
for (j = 0; j < g.n; j++)
{
g.edges[i, j] = a[i, j];///////////////////////////////////////////////
}
}
Console.WriteLine("各顶点的最短路径:");
}
static void initialVexInfo(MGraph g)
{
g.vexs[0].VexNo = "0361";
g.vexs[0].VexName = "西安";
g.vexs[1].VexNo = "010";
g.vexs[1].VexName = "北京";
g.vexs[2].VexNo = "0681";
g.vexs[2].VexName = "武汉";
g.vexs[3].VexNo = "0571";
g.vexs[3].VexName = "杭州";
}
static void Main(string[] args)
{
int i, j;
MGraph g;
g.n = 4; g.e = 8;
g.edges = new int[MAXV, MAXV];
g.vexs = new VertexType[MAXV];
initialVexInfo(g);
//int [,] anArray = new int [2, 4] {{1,2,3,4},{5,6,7,8}};
int[,] a = new int[MAXV, MAXV] {
{0, 5,INF,7},
{5, 0, 4,1},
{INF, 4, 0,INF},
{7,1,INF,0}
};
for (i = 0; i < g.n; i++) //建立图的图的邻接矩阵
{
for (j = 0; j < g.n; j++)
{
g.edges[i, j] = a[i, j];
}
}
Console.WriteLine("最小生成树构成:");
Dijkstra(g, 0);
Console.ReadKey();
}
}
}
