Difference between revisions of "Q1sol the solution"
| Line 1: | Line 1: | ||
| − | < | + | [[code type="c++"]] |
| − | < | + | //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, | //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. | ||
| Line 65: | Line 128: | ||
} | } | ||
| − | + | [[/code]] | |
Revision as of 17:13, 4 August 2010
code type="c++" //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;
}
