STL source code analysis-stl_stack.h

// Filename: stl_stack.h // comment by: Gel // E-mail: mdl2009@vip.qq.com // blog: http://blog.csdn.net/mdl13412////////////////////////////////////////////////////////////////////////////////// stack is a kind of advanced back-out (first in last out, Filo) data structure, which has only one exit // supports append to the top element of the stack, pop up, get, however, access to elements in other locations is not provided /////////////////////////////// //////////////////////////////////////// ///////// The following figure shows the layout when deque is used. /// the memory boundary reserved at the top of the current stack at the bottom of the stack // Please wait // ---------------------------------------------------------------------- // | ...... | ...... | x | // reserved memory | // | ----------------------------------- // | the reserved memory is not used yet, it may be 0 // | // only supports push (), pop (), top () operation /////////////////////////////////////// //////////////////////////////////////// // *** copyrig HT (c) 1994 * Hewlett-Packard Company ** permission to use, copy, modify, distribute and submit this software * and its documentation for any purpose is hereby granted without handle, * provided that the above copyright notice appear in all copies and * that both that copyright notice and this permission notice appear * in supporting documentation. hewlett-Packard Company makes no * representations AB Out the suitability of this software for any * purpose. it is provided "as is" without express or implied warranty. * ** copyright (c) 1996,1997 * Silicon Graphics Computer Systems, Inc. ** permission to use, copy, modify, distribute and merge this software * and its documentation for any purpose is hereby granted without tables, * provided that the above copyright notice appear in all copies and * That both that copyright notice and this permission notice appear * in supporting documentation. silicon Graphics makes no * representations about the suitability of this software for any * purpose. it is provided "as is" without express or implied warranty. * // * Note: This is an internal header file, encoded ded by other STL headers. * You shoshould not attempt to use it directly. */# ifndef _ sgi_stl_ I Nternal_stack_h # DEFINE _ sgi_stl_internal_stack_h1_stl_begin_namespace // If the compiler cannot deduce the default parameter type used later based on the preceding template parameters, // You must manually specify the parameter type, by default, deque is used in the internal container of the stack. // deque can be used dynamically when the storage space is insufficient and the cost is low # ifndef _ stl_limited_default_templatestemplate <class T, class sequence = deque <t> # elsetemplate <class T, class sequence> # endifclass stack {// special global operator, provide operator = and <overload to construct all operators // For details, see the description in <stl_pair.h> friend bool Operator ==_ _ Stl_null_tmpl_args (const stack &, const stack &); friend bool operator <_ stl_null_tmpl_args (const stack &, const stack &); public: // because the stack only supports operations on the top elements of the stack, do not define the STL required // pointer, iterator, difference_type typedef typename sequence: value_type; typedef typename sequence :: size_type; typedef typename sequence: Reference reference; typedef typename sequence: const_reference cons T_reference; protected: sequence C; // This is the public container we actually maintain: // The following operations are fully implemented using the member functions of the Internal container // This reflects the high reusability of STL again :-) // determine whether the stack is empty bool empty () const {return C. empty ();} // number of elements in the stack size_type size () const {return C. size () ;}// return the top element of the stack. Note that reference is returned here !!! Reference top () {return C. back ();} const_reference top () const {return C. back ();} // append the new element void push (const value_type & X) {C. push_back (x);} // remove the top element of the stack. Note that reference of the element is not returned. // many beginners often mistakenly think of POP () when using this container at random () the Operation also returns the reference void POP () {C. pop_back () ;}}; // to determine whether two stacks are equal, test whether internal maintenance containers are equal. // X. C = y. C will call the operator = template <class T, class sequence> bool operator = (const stack <t, sequence> & X, const stack <t, sequence> & Y) {return X. C = y. c;} template <class T, class sequence> bool operator <(const stack <t, sequence> & X, const stack <t, sequence> & Y) {return X. c <Y. c ;:__ stl_end_namespace # endif/* _ sgi_stl_internal_stack_h * // local variables: // mode: C ++ // end: