diff --git a/version0.7/lr_pda_demo.cpp b/version0.7/lr_pda_demo.cpp
deleted file mode 100644
index 4ee3972..0000000
--- a/version0.7/lr_pda_demo.cpp
+++ /dev/null
@@ -1,179 +0,0 @@
-#include <list>
-#include <stack>
-#include <cstring>
-#include <iostream>
-
-enum token_type
-{
-	S=1,a,T,__tri,__comma,__left_curve,__right_curve,sharp
-};
-
-const int max_len=5;
-struct cmp_seq
-{
-	int tokens[max_len];
-	int res;
-};
-cmp_seq par[]=
-{
-	{{a},                            S},
-	{{__tri},                        S},
-	{{__right_curve,T,__left_curve}, S},
-	{{S},                            T},
-	{{T,__comma,T},                  T},
-};
-int num_of_par=sizeof(par)/sizeof(cmp_seq);
-
-void print_token(int type)
-{
-	std::string context="";
-	switch(type)
-	{
-		case sharp:
-			context="#";
-			break;
-		case S:
-			context="S";
-			break;
-		case a:
-			context="a";
-			break;
-		case T:
-			context="T";
-			break;
-		case __tri:
-			context="^";
-			break;
-		case __comma:
-			context=",";
-			break;
-		case __left_curve:
-			context="(";
-			break;
-		case __right_curve:
-			context=")";
-			break;
-	}
-	std::cout<<context;
-	return;
-}
-
-class PDA
-{
-	private:
-		std::stack<int> main_stack;
-		std::stack<int> comp_stack;
-	public:
-		PDA(std::string& text)
-		{
-			main_stack.push(sharp);
-			for(int i=0;i<(int)text.length();++i)
-			{
-				if(text[i]=='(')
-					main_stack.push(__left_curve);
-				else if(text[i]==')')
-					main_stack.push(__right_curve);
-				else if(text[i]=='a')
-					main_stack.push(a);
-				else if(text[i]=='^')
-					main_stack.push(__tri);
-				else if(text[i]==',')
-					main_stack.push(__comma);
-			}
-			comp_stack.push(sharp);
-		}
-		void print_stack(std::stack<int>& temp)
-		{
-			std::stack<int> t;
-			while(!temp.empty())
-			{
-				t.push(temp.top());
-				print_token(t.top());
-				temp.pop();
-			}
-			while(!t.empty())
-			{
-				temp.push(t.top());
-				t.pop();
-			}
-			return;
-		}
-		void print_main_and_comp()
-		{
-			print_stack(main_stack);
-			std::cout<<"		";
-			print_stack(comp_stack);
-			std::cout<<std::endl;
-			return;
-		}
-		bool reducable()
-		{
-			std::stack<int> temp;
-			for(int i=0;i<num_of_par;++i)
-			{
-				for(int j=max_len-1;j>=0;--j)
-				{
-					if(!par[i].tokens[j])
-						continue;
-					// if par[i].tokens[j] is 0 then continue until the tokens[j] is not 0
-					temp.push(comp_stack.top());
-					comp_stack.pop();
-					if((par[i].tokens[j]!=temp.top()) || (comp_stack.empty() && par[i].tokens[j]))
-					{
-						while(!temp.empty())
-						{
-							comp_stack.push(temp.top());
-							temp.pop();
-						}
-						break;
-					}
-					if((par[i].tokens[j]==temp.top()) && (j==0))
-					{
-						comp_stack.push(par[i].res);
-						return true;
-					}
-				}
-			}
-			return false;
-		}
-		void work()
-		{
-			print_main_and_comp();
-			while(main_stack.top()!=sharp)
-			{
-				
-				comp_stack.push(main_stack.top());
-				main_stack.pop();
-				while(1)
-				{
-					if(!reducable())
-						break;
-					print_main_and_comp();
-				}
-			}
-			print_main_and_comp();
-			if(comp_stack.top()==T)
-			{
-				comp_stack.pop();
-				if(comp_stack.top()==sharp)
-					std::cout<<"accept."<<std::endl;
-				else
-					std::cout<<"error."<<std::endl;
-			}
-			else
-				std::cout<<"error."<<std::endl;
-			return;
-		}
-};
-
-int main()
-{
-	std::string text;
-	while(1)
-	{
-		std::cin>>text;
-		PDA m(text);
-		m.work();
-	}
-	return 0;
-}