Mercurial > Algorithms__Sedgewick
changeset 6:438f5608900e
Linked list based Stack class.
author | Eris Caffee <discordia@eldalin.com> |
---|---|
date | Fri, 29 May 2015 20:52:18 -0500 |
parents | 3db1a894bbdf |
children | a5052f77ba7e |
files | algs4-c++/src/Stack.cpp algs4-c++/src/Stack.hpp |
diffstat | 2 files changed, 210 insertions(+), 0 deletions(-) [+] |
line diff
1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 1.2 +++ b/algs4-c++/src/Stack.cpp Fri May 29 20:52:18 2015 -0500 1.3 @@ -0,0 +1,144 @@ 1.4 +// g++ -D STACK_MAIN -std=c++0x Stack.cpp 1.5 +// g++ -D STACK_MAIN -std=c++11 Stack.cpp 1.6 + 1.7 + 1.8 +#include "Stack.hpp" 1.9 + 1.10 +#include <cassert> 1.11 +#include <cstddef> 1.12 + 1.13 +#include <iostream> 1.14 + 1.15 +template <typename T> 1.16 +Stack<T>::Stack( void ) : 1.17 + N (0), 1.18 + list (nullptr) 1.19 + { 1.20 + } 1.21 + 1.22 +template <typename T> 1.23 +Stack<T>::~Stack( void ) { 1.24 + assert( N == 0 ); // Catch the potential memory leak. 1.25 + while ( list ) { 1.26 + Node * next = list->next; 1.27 + delete list; 1.28 + list = next; 1.29 + } 1.30 + } 1.31 + 1.32 +template <typename T> 1.33 +void Stack<T>::push( T &item ) { 1.34 + Node * node = new Node(); 1.35 + node->item = item; 1.36 + node->next = list; 1.37 + list = node; 1.38 + N++; 1.39 + } 1.40 + 1.41 +template <typename T> 1.42 +T Stack<T>::pop( void ) { 1.43 + assert( N > 0 ); 1.44 + 1.45 + T item = list->item; 1.46 + 1.47 + Node *old = list; 1.48 + list = list->next; 1.49 + delete old; 1.50 + N--; 1.51 + 1.52 + return item; 1.53 + } 1.54 + 1.55 +template <typename T> 1.56 +bool Stack<T>::is_empty( void ) { 1.57 + return N == 0; 1.58 + } 1.59 + 1.60 +template <typename T> 1.61 +size_t Stack<T>::size( void ) { 1.62 + return N; 1.63 + } 1.64 + 1.65 +template <typename T> 1.66 +typename Stack<T>::iterator Stack<T>::begin( void ) { 1.67 + return Stack<T>::iterator( list ); 1.68 + } 1.69 + 1.70 +template <typename T> 1.71 +typename Stack<T>::iterator Stack<T>::end( void ) { 1.72 + return Stack<T>::iterator( nullptr ); 1.73 + } 1.74 + 1.75 + 1.76 +//////////////////////////////////////////////////////////////////////////////// 1.77 + 1.78 +template <typename T> 1.79 +Stack<T>::iterator::iterator( Node *c ) : 1.80 + curr (c) 1.81 + { 1.82 + } 1.83 + 1.84 +template <typename T> 1.85 +typename Stack<T>::iterator & Stack<T>::iterator::operator++() { 1.86 + if ( this->curr != nullptr ) { 1.87 + this->curr = this->curr->next; 1.88 + } 1.89 + return *this; 1.90 + } 1.91 + 1.92 +template <typename T> 1.93 +typename Stack<T>::iterator Stack<T>::iterator::operator++( int ) { 1.94 + auto t = Stack<T>::iterator( *this ); 1.95 + 1.96 + if ( this->curr != nullptr ) { 1.97 + this->curr = this->curr->next; 1.98 + } 1.99 + return t; 1.100 + } 1.101 + 1.102 +template <typename T> 1.103 +T Stack<T>::iterator::operator*() { 1.104 + return this->curr->item; 1.105 + } 1.106 + 1.107 +template <typename T> 1.108 +bool Stack<T>::iterator::operator!=( typename Stack<T>::iterator other ) { 1.109 + return this->curr != other.curr; 1.110 + } 1.111 + 1.112 + 1.113 +//////////////////////////////////////////////////////////////////////////////// 1.114 + 1.115 +#ifdef STACK_MAIN 1.116 + 1.117 +#include <iostream> 1.118 + 1.119 +int main ( int argc, char **argv ) { 1.120 + 1.121 + Stack<long> stack; 1.122 + 1.123 + long i; 1.124 + while ( ! std::cin.eof() ) { 1.125 + std::cin >> i; 1.126 + if ( std::cin.good() ) 1.127 + stack.push(i); 1.128 + } 1.129 + 1.130 + std::cout << "Stack has " << stack.size() << " entries." << std::endl; 1.131 + 1.132 + for ( auto iter = stack.begin(); iter != stack.end(); ++iter ) { 1.133 + std::cout << *iter << std::endl; 1.134 + } 1.135 + 1.136 + std::cout << "Popping entries..." << std::endl; 1.137 + 1.138 + while ( ! stack.is_empty() ) { 1.139 + i = stack.pop(); 1.140 + std::cout << i << std::endl; 1.141 + } 1.142 + 1.143 + std::cout << "Stack has " << stack.size() << " entries." << std::endl; 1.144 + 1.145 + } 1.146 + 1.147 +#endif
2.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000 2.2 +++ b/algs4-c++/src/Stack.hpp Fri May 29 20:52:18 2015 -0500 2.3 @@ -0,0 +1,66 @@ 2.4 +#ifndef STACK_HPP 2.5 +#define STACK_HPP 2.6 + 2.7 +#include <cstddef> 2.8 + 2.9 +// Linked list based stack after Sedgewick and Wayne, Algorithms 4th ed, Algorithm 1.2 2.10 + 2.11 +template <typename T> 2.12 +class Stack { 2.13 + 2.14 +public: 2.15 + 2.16 + //////////////////////////////////// 2.17 + class Node { 2.18 + public: 2.19 + T item; 2.20 + Node *next; 2.21 + }; 2.22 + 2.23 + 2.24 + //////////////////////////////////// 2.25 + class iterator; 2.26 + friend class iterator; 2.27 + class iterator { 2.28 + 2.29 + public: 2.30 + 2.31 + iterator( Node *c ); 2.32 + 2.33 + iterator& operator++(); 2.34 + iterator operator++(int); 2.35 + 2.36 + T operator*(); 2.37 + bool operator!=( typename Stack<T>::iterator ); 2.38 + 2.39 + private: 2.40 + 2.41 + Node *curr; 2.42 + }; 2.43 + 2.44 + //////////////////////////////////// 2.45 + 2.46 + Stack( void ); 2.47 + ~Stack( void ); 2.48 + 2.49 + void push( T &item ); 2.50 + T pop( void ); 2.51 + 2.52 + bool is_empty( void ); 2.53 + size_t size( void ); 2.54 + 2.55 + iterator begin( void ); 2.56 + iterator end( void ); 2.57 + 2.58 +private: 2.59 + 2.60 + size_t N; 2.61 + Node *list; 2.62 + 2.63 + void resize( size_t new_max ); 2.64 + }; 2.65 + 2.66 + 2.67 + 2.68 +#endif 2.69 +