using System; 
 using System.Collections.Generic; 
 //using System.Linq; 
 using System.Text; 
 namespace Exame 
 { 
 	//表达式节点， 
 	//其中Exp可以表示为对其他节点的引用，格式为['NodeName']的形式，比如['a']+['b']表示 Name=="a"的节点的值 “加上” Name="b"的节点的值 
 	public struct ExpNode 
 	{ 
 		public string Name;  //名称 
 		public string Exp;  //表达式：可以为直接量：比如：12，30.0.也可能为表达式：['a']+['b']. 
 		public ExpNode(string name, string exp) 
 		{ 
 			this.Name = name; 
 			this.Exp = exp; 
 		} 
 		public override string ToString() 
 		{ 
 			return Name; 
 		} 
 	} 
 	 
 	class Program 
 	{ 
 		static void Main(string[] args) 
 		{ 
 			ExpNode[] nodes = new ExpNode[] 
 			{ 
 				new ExpNode("a","['b']+['c']"), 
 				new ExpNode("b","['e']-['c']"), 
 				new ExpNode("c","['e']+['d']"), 
 				new ExpNode("d","10"), 
 				new ExpNode("e","['d']+2"), 
 				 
 			}; 
 			 
 			/*************************************************************************/ 
 			 
 			 
 			Dictionary <string,int> nodeindex=new Dictionary <string,int>(); 
 			//建立节点名字索引关联 
 			int count=0; 
 			foreach(ExpNode node in nodes) 
 			{ 
 				nodeindex.Add(node.Name,count++); 
 			} 
 			 
 			//建立节点拓扑邻接矩阵 
 			int[,] map=new int[nodes.Length,nodes.Length]; 
 			Array.Clear(map,0,nodes.Length*nodes.Length); 
 			foreach(ExpNode node in nodes) 
 			{ 
 				if(node.Exp.Contains("+")||node.Exp.Contains("-")) 
 				{ 
 					string[] temp=node.Exp.Split(new char[]{'+','-'},StringSplitOptions.RemoveEmptyEntries); 
 					foreach(string s in temp) 
 					{    
 						if(s.Contains(&q