astack.h

用栈、顺序表实现四则运算

#ifndef ASTACK_H_H
#define ASTACK_H_H

template<class Elem>class AStack{
	public:
		int size;
		int top;
		Elem* listArray;
	public:
		AStack(int sz=DefaultListSize)
		{size=sz;top=0;listArray=new Elem[sz];}
		~AStack(){delete [] listArray;}
		void clear(){top=0;}
		bool push(const Elem& item){
			if(top==size) return false;
			else{listArray[top++]=item;return true;}
		}
		bool pop(Elem& item){
			if(top==0) return false;
			else{item=listArray[--top];return true;}
		}
		bool topValue(Elem& it)const{
			if(top==0) return false;
			else{it=listArray[top-1];return true;}
		}
		int length()const{return top;}
};

#endif