【发布时间】：2015-01-12 00:13:01
【问题描述】：
我在将中缀转换为后缀时遇到问题这是我的代码它接受字符中缀输入但不显示任何后缀输出请告诉我是什么问题我一直在尝试解决但我发现没有问题我会如果有人发现问题，非常感谢你。另一件事是我如何也可以添加 {} 和 [] 这个括号？
#include <iostream>
#include<string.h>
using namespace std;
template <class T>
class Node
{
public:
T info;
Node *ptrnext;
Node *ptrprevious;
Node()
{
info = 0;
ptrnext = 0;
ptrprevious = 0;
}
Node(T e, Node *n, Node *p)
{
info = e;
ptrnext = n;
ptrprevious = p;
}
};
template <class T>
class DLinkedList
{
private:
Node<T> *head;
Node<T> *tail;
public:
DLinkedList()
{
head = 0;
tail = 0;
}
bool isEmpty();
void addToHead(T e);
void addToTail(T e);
void deleteFromHead();
void deleteFromTail();
void display();
T getHead();
int numofNodes();
~DLinkedList(){
if(!isEmpty())
{
while(head!=0){
if(head==tail)
{
delete head;
head=0;
tail=0;
}
else{
Node<T> *ptrtemp=head;
head=head->ptrnext;
head->ptrprevious=NULL;
delete ptrtemp;
}
}
}
}
};
template <class T>
bool DLinkedList<T>::isEmpty()
{
if (head == 0)
{
return true;
}
else
{
return false;
}
}
template <class T>
void DLinkedList<T>::addToHead(T e)
{
Node<T> *ptrnode = new Node<T>(e,0,0);
if(isEmpty())
{
head = ptrnode;
tail = ptrnode;
}
else
{
ptrnode->ptrnext = head;
head->ptrprevious = ptrnode;
ptrnode->ptrprevious = 0;
head = ptrnode;
}
}
template <class T>
void DLinkedList<T>::addToTail(T e)
{
Node<T> *ptrnode = new Node<T>(e,0,0);
if(isEmpty())
{
head = ptrnode;
tail = ptrnode;
}
else
{
tail->ptrnext = ptrnode;
ptrnode->ptrprevious = tail;
ptrnode->ptrnext = 0;
tail = ptrnode;
}
}
template <class T>
void DLinkedList<T>::deleteFromHead()
{
if(!isEmpty())
{
if(head == tail)
{
delete head;
head = 0;
tail = 0;
}
else
{
Node<T> *ptrtemp = head;
head = head->ptrnext;
head->ptrprevious = 0;
delete ptrtemp;
}
}
}
template <class T>
void DLinkedList<T>::deleteFromTail()
{
if(!isEmpty())
{
if(head == tail)
{
delete tail;
head = 0;
tail = 0;
}
else
{
Node<T> *ptrtemp = tail;
tail = tail->ptrprevious;
tail->ptrnext = 0;
delete ptrtemp;
}
}
}
template <class T>
void DLinkedList<T>::display()
{
if(!isEmpty())
{
Node<T> *ptrtemp = head;
while(ptrtemp->ptrnext != 0)
{
cout<<ptrtemp->info;
ptrtemp = ptrtemp->ptrnext;
}
cout<<ptrtemp->info<<endl;
}
}
template <class T>
T DLinkedList<T>::getHead()
{
if(isEmpty())
{
return 0;
}
else
{
return head->info;
}
}
template <class T>
int DLinkedList<T>::numofNodes()
{
if(isEmpty())
{
return 0;
}
else
{
int count = 0;
Node<T> *ptrtemp = head;
while(ptrtemp->ptrnext != 0)
{
count++;
ptrtemp = ptrtemp->ptrnext;
}
count++;
return count;
}
}
template <class T>
class Stack:public DLinkedList<T>
{
private:
int maxStackSize;
public:
Stack()
{
maxStackSize = 10;
}
bool isEmpty();
bool isFull();
void Push(T e);
T Pop();
void display();
T topvalue();
};
template <class T>
bool Stack<T>::isEmpty()
{
bool r= DLinkedList<T>::isEmpty();
return r;
}
template <class T>
bool Stack<T>::isFull()
{
int totalNodes = DLinkedList<T>::numofNodes();
if(totalNodes == maxStackSize)
{
return true;
}
else
{
return false;
}
}
template <class T>
void Stack<T>::Push(T e)
{
if( isFull() )
{
cout<<"Stack Full "<<endl;
}
else
{
DLinkedList<T>::addToHead(e);
}
}
template <class T>
T Stack<T>::Pop()
{
if(isEmpty())
{
return 0;
}
else
{
T n = DLinkedList<T>::getHead();
DLinkedList<T>::deleteFromHead();
return n;
}
}
template <class T>
void Stack<T>::display()
{
if( isEmpty() )
{
cout<<"Stack Empty!!"<<endl;
}
else
{
DLinkedList<T>::display();
}
}
template<class T>
T Stack<T>::topvalue()
{
T temp;
temp=DLinkedList<T>::getHead();
return temp;
}
int main()
{
Stack<char> obj;
char input[20];
cout<<"Enter Values \n";
cin>>input;
int size= strlen(input);
for(int i=0; i <size ; i++)
{
//======= For + or - Operators=========
if(input[i]=='+' || input[i]=='-')
{
if(obj.topvalue()=='+' || obj.topvalue()=='-')
{ //======= CASE-1=======
cout<<obj.Pop();
obj.Push(input[i]);
}
else if(obj.topvalue()=='*' || obj.topvalue()=='/')
{
//======= CASE-2=========
cout<<obj.Pop();
if(obj.topvalue()=='*' || obj.topvalue()=='/')
{
cout<<obj.Pop();
}
obj.Push(input[i]);
}
else if(obj.topvalue()=='(')
{
//======= CASE-3=========
obj.Push(input[i]);
}
else if(obj.isEmpty())
{
//======= CASE-4=========
obj.Push(input[i]);
}
}
// ++++++++++ FOR * and / Operators ++++++++
else if(obj.topvalue()=='*' || obj.topvalue()=='/')
{
if(obj.topvalue()=='+' || obj.topvalue()=='-')
{
//======= CASE-1=========
cout<<obj.Pop();
obj.Push(input[i]);
}
else if(obj.isEmpty())
{
//======= CASE-2=========
obj.Push(input[i]);
}
else if(obj.topvalue()=='(')
{
//======= CASE-3=========
obj.Push(input[i]);
}
else
{
//======= CASE-4=========
obj.Push(input[i]);
}
}
// ++++++++++ Opening bracket ++++++++
else if (obj.topvalue()=='(')
{
obj.Push(input[i]);
}
// ++++++++++ Closing Bracket ++++++++
else if(input[i] != ')')
{
while(obj.topvalue() != '(')
{
cout<<obj.Pop();
}
obj.Pop();
}
// ++++++++++ Operands ++++++++
else
{
cout<<input[i];
}
}
// ++++++++++ Print All values from the Stack and empty it++++++++
while(!obj.isEmpty())
{
cout<<obj.Pop();
}
return 0;
}
>
【问题讨论】：
-
不完全是 sscce。
-
@Bathsheba 我没听懂你？
-
@MuhammadUsman - 有什么理由不使用
std::list或std::stack？即使有借口，也要使用 std::list 来验证您的算法是否有效。然后回去用你自制的容器类替换它。 -
在循环中为转换定义了整个案例@didierc
标签： c++ stack doubly-linked-list