Difference between revisions of "Q1sol the solution"
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| − | < | + | <source lang="c++"> |
//to write a linked list like structure, you must begin with a node. Without the node, | //to write a linked list like structure, you must begin with a node. Without the node, | ||
//you can't have a linked list. | //you can't have a linked list. | ||
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return rc; | return rc; | ||
} | } | ||
| − | </ | + | </source> |
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Revision as of 18:19, 4 August 2010
//to write a linked list like structure, you must begin with a node. Without the node,
//you can't have a linked list.
template <class T>
struct Node{
T data_;
Node<T>* next_;
};
template <class T>
class Stack{
Node<T>* start_;
public:
/*this constructor initializes the stack to an empty stack*/
Stack();
/*this function adds a piece of data of type T to the stack and returns
nothing*/
void push(T data);
/*removes and returns a piece of data from the stack. If the stack is
empty throw the string "empty stack"*/
T pop()
/*returns true if empty, false otherwise*/
bool isempty();
};
template <class T>
Stack<T>::Stack(){
start_=NULL;
}
template <class T>
void Stack<T>::push(T data){
Node<T>* nn;
nn=new Node<T>;
nn->data_=data;
nn->next_=start_;
start_=nn;
}
template <class T>
T Stack<T>::pop(){
T rc;
if(isempty()){
throw "Empty Stack";
}
else{ //this else is optional because if you throw an exception,rest
rc=start_->data_;
Node<T>* rm=start_;
start_=start_->next;
delete rm;
}
return rc;
}
template <class T>
bool Stack<T>::isempty(){
bool rc=true;
if(start_){
rc=false;
}
return rc;
}
//to write a linked list like structure, you must begin with a node. Without the node,
//you can't have a linked list.
template <class T>
struct Node{
T data_;
Node<T>* next_;
};
template <class T>
class Stack{
Node<T>* start_;
public:
/*this constructor initializes the stack to an empty stack*/
Stack();
/*this function adds a piece of data of type T to the stack and returns
nothing*/
void push(T data);
/*removes and returns a piece of data from the stack. If the stack is
empty throw the string "empty stack"*/
T pop()
/*returns true if empty, false otherwise*/
bool isempty();
};
template <class T>
Stack<T>::Stack(){
start_=NULL;
}
template <class T>
void Stack<T>::push(T data){
Node<T>* nn;
nn=new Node<T>;
nn->data_=data;
nn->next_=start_;
start_=nn;
}
template <class T>
T Stack<T>::pop(){
T rc;
if(isempty()){
throw "Empty Stack";
}
else{ //this else is optional because if you throw an exception,rest
rc=start_->data_;
Node<T>* rm=start_;
start_=start_->next;
delete rm;
}
return rc;
}
template <class T>
bool Stack<T>::isempty(){
bool rc=true;
if(start_){
rc=false;
}
return rc;
}