File indexing completed on 2024-04-21 03:41:49
0001 /* 0002 PrimeNumber.cpp - source code of class PrimeNumber 0003 SPDX-FileCopyrightText: 2001 Sebastian Stein <seb.kde@hpfsc.de> 0004 0005 SPDX-License-Identifier: GPL-2.0-or-later 0006 */ 0007 0008 #ifndef PRIMENUMBER_H 0009 #define PRIMENUMBER_H 0010 0011 #include <QList> 0012 0013 typedef QList<uint> UnsignedIntArray; 0014 0015 /** Class to handle prime numbers. 0016 * The prime numbers are stored in a static vector, so that different instances 0017 * can use them. Each time a higher prime number is needed, the new found prime 0018 * number is stored in the vector. To check if a given number is a prime number 0019 * this vector is scanned and if needed new prime numbers are generated. This 0020 * algorithm should reduce calculation time and speed up every program using 0021 * this prime number class. 0022 * \author Sebastian Stein */ 0023 class PrimeNumber 0024 { 0025 public: 0026 /** constructor */ 0027 PrimeNumber(); 0028 0029 /** destructor */ 0030 ~PrimeNumber(); 0031 0032 /** returns whether the given number is a prime number */ 0033 short isPrimeNumber(uint number); 0034 0035 /** returns the next prime number */ 0036 unsigned int get_next(); 0037 0038 /** returns the first prime number */ 0039 unsigned int get_first() const; 0040 0041 /** return the last known prime number */ 0042 unsigned int get_last() const; 0043 0044 /** returns the current prime number */ 0045 unsigned int get_current() const; 0046 0047 /** moves the internal pointer to the first prime number */ 0048 void move_first(); 0049 0050 /** moves the internal pointer to the last prime number */ 0051 void move_last(); 0052 0053 /** moves the internal pointer to the next prime number */ 0054 void move_forward(); 0055 0056 /** moves the internal pointer to the previous prime number */ 0057 void move_back(); 0058 0059 /** Displays all known prime numbers, mainly used for debugging. */ 0060 void display_all(); 0061 private: 0062 /** a vector storing all known prime numbers, access for all objects; 0063 * we are using the vector<T> template; so we do not have to think 0064 * about dynamic mem manipulation */ 0065 static UnsignedIntArray prim_vector; 0066 0067 /** current selected prime number */ 0068 UnsignedIntArray::iterator current_pos; 0069 0070 /** finds next prime number and adds it to the vector */ 0071 void find_next(); 0072 }; 0073 #endif