List.hpp

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#ifndef HEADER_LIST
#define HEADER_LIST
 
#include <istream>
#include <ostream>
 
template <typename T>
class List {
protected:
    T* elements;
    unsigned length;
    unsigned count;
 
    void resize();
    void free();
    void copyFrom(const List& other);
 
public:
    List(const T* elements, unsigned elementsCount);
    void add(const T& element);
    void insertAt(const T& element, unsigned index);
    bool removeAt(unsigned index);
    unsigned findIndex(const T& element) const;
    bool contain(const T& element) const;
    T& operator[](unsigned index);
    const T& operator[](unsigned index) const;
 
    List<T>& operator+=(const List<T> other);
 
    std::istream& read(std::istream& istr);
    std::ostream& write(std::ostream& ostr) const;
 
    unsigned get_length() const;
    unsigned get_count() const;
 
    List();
    List& operator=(const List& other);
    List(const List& other);
    ~List();
 
    List(List&& other);
    List& operator=(List&& other);
};
 
template <typename T>
std::istream& operator>>(std::istream& istr, List<T>& obj);
template <typename T>
std::ostream& operator<<(std::ostream& ostr, const List<T>& obj);
 
/* Private */
 
template <typename T>
void List<T>::resize() {
    length = (length == 0) ? 8 : length << 1;
    T* temp = new T[length];
    for (int i = 0; i < count; i++)
        temp[i] = elements[i];
    delete[] elements;
    elements = temp;
}
 
template <typename T>
void List<T>::free() {
    delete[] elements;
}
 
template <typename T>
void List<T>::copyFrom(const List& other) {
    elements = new T[other.length];
    for (int i = 0; i < other.count; i++)
        elements[i] = other.elements[i];
    length = other.length;
    count = other.count;
}
 
/* Public */
 
template <typename T>
List<T>::List(const T* elements, unsigned elementsCount) {
    length = 8;
    count = elementsCount;
    this->elements = new T[length];
    for (unsigned i = 0; i < count; i++)
        this->elements[i] = elements[i];
}
 
template <typename T>
void List<T>::add(const T& element) {
    if (length == count) resize();
 
    elements[count++] = element;
}
 
template <typename T>
void List<T>::insertAt(const T& element, unsigned index) {
    if (index >= count) {
        add(element);
        return;
    }
    if (length == count) resize();
 
    for (unsigned i = count; i > index; i--)
        elements[i] = elements[i - 1];
 
    elements[index] = element;
    count++;
}
 
template <typename T>
bool List<T>::removeAt(unsigned index) {
    if (index >= count) return false;
 
    for (int i = index; i < count; i++)
        elements[i] = elements[i + 1];
    count--;
    return true;
}
 
template <typename T>
unsigned List<T>::findIndex(const T& element) const {
    unsigned ind = 0;
    while (ind < count && elements[ind].compare(element) != 0)
        ind++;
    return ind;
}
 
template <typename T>
bool List<T>::contain(const T& element) const {
    return findIndex(element) < count;
}
 
template <typename T>
T& List<T>::operator[](unsigned index) {
    return elements[index];
}
 
template <typename T>
const T& List<T>::operator[](unsigned index) const {
    return elements[index];
}
 
template <typename T>
List<T>& List<T>::operator+=(const List<T> other) {
    for (unsigned i = 0; i < other.length; i++)
        add(other[i]);
    return *this;
}
 
template <typename T>
std::istream& List<T>::read(std::istream& istr) {
    istr.read((char*)&length, sizeof(length));
    istr.read((char*)&count, sizeof(count));
 
    delete[] elements;
    elements = new T[length];
 
    for (int i = 0; i < count; i++)
        elements[i].read(istr);
 
    return istr;
}
 
template <typename T>
std::ostream& List<T>::write(std::ostream& ostr) const {
    ostr.write((const char*)&length, sizeof(length));
    ostr.write((const char*)&count, sizeof(count));
 
    for (int i = 0; i < count; i++)
        elements[i].write(ostr);
 
    return ostr;
}
 
template <typename T>
unsigned List<T>::get_length() const {
    return length;
}
 
template <typename T>
unsigned List<T>::get_count() const {
    return count;
}
 
// Rule of 4
 
template <typename T>
List<T>::List() : List(nullptr, 0) {}
 
template <typename T>
List<T>& List<T>::operator=(const List& other) {
    if (this != &other) {
        free();
        copyFrom(other);
    }
    return *this;
}
 
template <typename T>
List<T>::List(const List& other) {
    copyFrom(other);
}
 
template <typename T>
List<T>::~List() {
    free();
}
 
// Move semantics
 
template <typename T>
List<T>::List(List&& other) {
    length = other.length;
    count = other.count;
    elements = other.elements;
    other.elements = nullptr;
}
 
template <typename T>
List<T>& List<T>::operator=(List&& other) {
    if (this != &other) {
        free();
        length = other.length;
        count = other.count;
        elements = other.elements;
        other.elements = nullptr;
    }
    return *this;
}
 
/* Outside of class */
 
template <typename T>
std::istream& operator>>(std::istream& istr, List<T>& obj) {
    List<T> newObj;
    unsigned count;
    istr >> count;
 
    T temp;
    for (int i = 0; i < count; i++) {
        istr >> temp;
        obj.add(temp);
    }
 
    return istr;
}
 
template <typename T>
std::ostream& operator<<(std::ostream& ostr, const List<T>& obj) {
    ostr << obj.get_count() << std::endl;
    for (int i = 0; i < obj.get_count(); i++)
        ostr << obj[i];
 
    return ostr;
}
 
 
#endif