//////////////////// // // Name: Class Array2D // Author: Shadow // Version: 1.0.0 // Date: 13/01/2018 // Description: My own two-dimensional array class // Planned: // //////////////////// // //////////PREPROCESSOR////////// // #include #include // std::size_t #include // assert() // //////////CLASSES////////// // template class Array2D { private: std::size_t rows; std::size_t columns; T* ptr; //the values are stored in a single-dimensional array to which ptr points //Access: rows * columns + columns //Reason: same speed, but ctor & dtor are easier to write because I dont have to maintain a pointer to pointers to the actual array with new and delete public: Array2D(std::size_t r, std::size_t c) :rows(r), columns(c), ptr{new T[r * c]} //same as: T* ptr = new T[r * c]; {} Array2D(std::size_t r, std::size_t c, const T& value) :Array2D(r, c) {init(value);} Array2D(const Array2D& arr) :Array2D(arr.rows, arr.columns) { std::size_t anzahl = rows * columns; for (std::size_t i = 0; i < anzahl; ++i) { ptr[i] = arr.ptr[i]; } } //upon destruction, free the resources ~Array2D() { delete[] ptr; } //instead of copying every single value per hand, use swap with a copy of the array I want to have the values from Array2D& assign(Array2D tmp) { swap(tmp); return *this; } inline std::size_t getRows() const {return rows;} inline std::size_t getColumns() const {return columns;} double getSum() { double sum {}; std::size_t anzahl = rows * columns; for (std::size_t i = 0; i < anzahl; ++i) { sum += ptr[i]; } return sum; } T getMax() const { T maxValue = (*this).ptr[0]; std::size_t anzahl = rows * columns; for (std::size_t i = 0; i < anzahl; ++i) { if (ptr[i] > maxValue) {maxValue = ptr[i];} } return maxValue; } T getMin() const { T minValue = (*this).ptr[0]; std::size_t anzahl = rows * columns; for (std::size_t i = 0; i < anzahl; ++i) { if (ptr[i] < minValue) {minValue = ptr[i];} } return minValue; } //fill entire array with one value void init(const T& value) { std::size_t anzahl = rows * columns; for (std::size_t i = 0; i < anzahl; ++i) { ptr[i] = value; } } //access on elements read-only const T& at(const std::size_t r, const std::size_t c) const { assert(r < rows && c < columns); return ptr[r * columns + c]; } //access on elements for changes T& at(const std::size_t r, const std::size_t c) { assert(r < rows && c < columns); return ptr[r * columns + c]; } //Rule of the Three: //If you code your own copy ctor, dtor or assignment operator, also code both others Array2D& operator=(T& value) { this->ptr = value; return *this; } //swap values from *this with rhs void swap(Array2D& rhs) { std::size_t temp = rows; rows = rhs.rows; temp = columns; columns = rhs.columns; rhs.columns = temp; T* tempPtr = ptr; ptr = rhs.ptr; rhs.ptr = tempPtr; } void printArray() { for (std::size_t r = 0; r < (*this).rows; ++r) { for (std::size_t c = 0; c < (*this).columns; ++c) { std::cout << (*this).at(r, c) << " "; } std::cout << "\n"; } std::cout << std::endl; } }; // //////////MAIN FUNCTION////////// // int main() { //just some sample code Array2D arr1(2, 2, 1); arr1.printArray(); for (std::size_t i = 0; i < arr1.getRows(); ++i) { for (std::size_t j = 0; j < arr1.getColumns(); ++j) { arr1.at(i, j) = i + j; } } Array2D arr2(arr1); arr1.printArray(); arr2.init(3); arr1.swap(arr2); arr1.printArray(); arr2.printArray(); std::cout << arr1.getSum() << "\n" << arr2.getSum() << "\n" << std::endl; arr2.at(0, 0) = arr2.at(1, 1) = arr1.getMax(); arr2.printArray(); return 0; }

Array2D Class