棧--括號匹配

#include <iostream>
using namespace std;
class Ele{
private:

public:
	char data;
	Ele* next;
	//Ele(void);
	//~Ele(void);
	void setData(int d){
		data=d;
	}
	void setNext(Ele* p){
		next=p;
	}
};
class Stack{
private:
	
public:
	Ele* first;
	int length;
	Stack(){
		first=NULL;
		length=0;
	}
	//~Stack();
	void create(int len){
		for(int i=0;i<len;i++){
			Ele* p=new Ele();
			p->data=i;
			p->next=NULL;
			push(p);
			length++;
		}		

	}

	void push(Ele* e){
		if(ifEmpty()){
			first=e;
		}
		else{
			e->next=first;
			first=e;
		}
		length++;
	}
	Ele* pop(){
		Ele* p=NULL;
		if(!ifEmpty()){
			p=first;
			first=first->next;
			p->next=NULL;
			length--;
		}
		return p;
	}
	bool ifEmpty(){
		if(length==0)return true;
		else return false;
	}

};
bool check(char c1,char c2){
	switch(c1){
	case '(':if(c2==')')return true;break;
	case '{':if(c2=='}')return true;break;
	case '[':if(c2==']')return true;break;
	}
	return false;
}

int main(){
	Stack sta;
	char c;
	int mark=0;
	cin.get(c);
	while(c!='\n'){
		//cout<<"c:"<<c<<"mark:"<<mark<<endl;
		if(c=='{'||c=='('||c=='['){
			Ele* p=new Ele();
			p->data=c;
			p->next=NULL;
			sta.push(p);
			//cout<<"push is ok"<<endl;
		}else if(c=='}'||c==']'||c==')')
		{
			//cout<<"length:"<<sta.length<<endl;
			if(!sta.ifEmpty()){
				Ele* q=sta.pop();
				//cout<<"pop:"<<q->data<<"c:"<<endl;
				if(!check(q->data,c))
					mark=1;
			}else 
				mark=2;

		}
		cin.get(c);
	}
	switch(mark){
	case 0:cout<<"匹配成功"<<endl;break;
	case 1:cout<<"匹配錯誤"<<endl;break;
	case 2:cout<<"括號缺失"<<endl;break;}
	system("pause");
	return 0;
}