Vector klasės implementacija

Užpildymo greičio palyginimas

10000 std::vector: 0 100000 std::vector: 0.002001 1000000 std::vector: 0.015012 10000000 std::vector: 0.165038

10000 Mano vektorius: 0 100000 Mano vektorius: 0.001001 1000000 Mano vektorius: 0.013003 10000000 Mano vektorius: 0.176933

begin() funkcija

Funkcija gražinanti pirmą reikšmę

Funkcija: T& begin() { return arr[0]; }

Testas:

MyVector test; test.push_back(1); test.push_back(2); test.push_back(3); cout << "Pirmas elementas: " << test.begin() << endl << endl;

Output:

Pirmas elementas: 1

shrink_to_fit() funkcija

Funkcija:

void shrink_to_fit() { capacity = current; T* newarr = new T[capacity]; for (int i = 0; i < capacity; i++) { newarr[i] = arr[i]; } delete[] arr; arr = newarr; }

Testas:

MyVector test2; test2.push_back(1); test2.push_back(2); test2.push_back(3);

cout << "Capacity pries Shrink_To_Fit: " << test2.getcapacity() << endl;

test2.shrink_to_fit(); cout << "Capacity po Shrink_To_Fit: " << test2.getcapacity() << endl;

Output:

Capacity pries Shrink_To_Fit: 4 Capacity po Shrink_To_Fit: 3

operator=

Funkcija

MyVector& operator =(const MyVector& temp)//= operatorius { if (temp.elKiekis > elKiekis) { delete[] arr; talpa = temp.elKiekis; arr = new int[talpa]; } for (int i = 0; i < temp.elKiekis; i++) { arr[i] = temp.arr[i]; }

	elKiekis = temp.elKiekis;

	return *this;
}

Testas:

MyVector test3; MyVector copy; test3.push_back(1); test3.push_back(2); copy = test3; cout << "Copy elementai: "; copy.print();

Output:

Copy elementai: 1 2

erase() funkcija

Funkcija:

void erase(int index) { for (int i = index; i < current - 1; i++) { arr[i] = arr[i + 1]; } current--; }

Testas:

MyVector test4; test4.push_back(1); test4.push_back(2); test4.push_back(3); cout << "Pradiniai elementai: "; test4.print();

test4.erase(1); cout << "Elementai po trynimo: "; test4.print();

Output:

Pradiniai elementai: 1 2 3 Elementai po trynimo: 1 3

pop_back() funkcija

Funkcija:

void pop_back() { current--; }

Testas:

MyVector test5; test5.push_back(1); test5.push_back(2); test5.push_back(3); cout << "Pradiniai elementai: "; test5.print();

test5.pop_back(); cout << "Elementai po pop_back: "; test5.print();

Output:

Pradiniai elementai: 1 2 3 Elementai po pop_back: 1 2

Atminties perskirstymas

Testas:

unsigned int sz = 100000000; int p1 = 0, p2 = 0;

vector v1; for (int i = 1; i <= sz; ++i) { v1.push_back(i); if (v1.size() == v1.capacity()) p1++; }

MyVector v2; for (int i = 1; i <= sz; ++i) { v2.push_back(i); if (v2.size() == v2.gettalpa()) p2++; } cout << "std::vector: " << p1 << endl; cout << "MyVector: " << p2 << endl;

output:

std::vector: 27 MyVector: 27