c05p245.txt

Data Abstraction & Problem Solving with C++源码

template <class T> class std::vector
{
public:
   vector()
   // Default constructor
   // Precondition: None.
   // Postcondition: An empty vector exists.

   vector(size_type n)
   // Creates a vector with n elements
   // Precondition: None.
   // Postcondition: A vector of n elements exists.

   bool empty() const;
   // Determines whether the vector is empty.
   // Precondition: None.
   // Postcondition: Returns true if the vector is empty,
   // otherwise returns false.

   size_type size() const;
   // Determines the length of the vector.
   // The return type size_type is an integral type. 
   // Precondition: None.
   // Postcondition: Returns the number of items that
   // are currently in the vector.

   void push_back(const T&);
   // Inserts a new element at the end of the vector.
   // Precondition: None.
   // Postcondition: The new element is the last element
   // in the vector.

   void pop_back();
   // Removes the last element of the vector.
   // Precondition: There is at least one element in the vector.
   // Postcondition: The last element of the vector is removed.

   iterator insert(iterator i, const T& val);	
   // Inserts an item val into the vector.
   // before the element specified by the iterator i.  
   // Precondition: The iterator is initialized.
   // Postcondition: Item val is inserted into the vector and
   // an iterator to the newly inserted item is returned.    

   iterator erase(iterator i);
   // Removes element at i.
   // Precondition: The iterator must be initialized.
   // Postcondition: Returns an iterator to the item 
   // following the removed item. 

   void clear();
   // Erases all the elements in the vector.
   // Precondition: None.
   // Postcondition: The vector has no elements. 

   iterator begin();
   // Returns an iterator to the first element in the
   // vector.
   // Precondition: None.
   // Postcondition: If the vector is empty,
   // the value returned by end() is returned. 

   iterator end();
   // Returns an iterator to test for the end of the
   // vector.
   // Precondition: None.
   // Postcondition: The value for the end of the vector was
   // returned.

}  // end STL vector