lesson_321_21

#include <iostream>

using namespace std;

// ф-я с аргументом по умолчанию
int sum(int a, int b, int c = 0) {
    return a + b + c;
}

void task0() {
    int d = 5;
    double x = 17.5;
    bool arr[]{ true, false, true, false };

    cout << &d << " " << &x << endl;
    cout << arr << " " << &(arr[0]) << endl;
    cout << sum << endl;

    double* px = &x, *py = &x;
    int* pd = &d;
    cout << px << " " << pd << endl;
    bool* pArr = &(arr[0]);
    cout << pArr << endl;

    cout << px << " " << *px << " "
        << typeid(*px).name() << " "
        << x << endl; // оп разъименования

    // *px - это l-value
    *px = 55.123;
    cout << px << " " << *px << " " << x << endl;

    double very_long_name_for_my_variable = 15.123;

    // Указатель, pointer
    double* pVal;
    pVal = &very_long_name_for_my_variable;
    cout << *pVal << endl;

    // Ссылка, reference
    double& Val = very_long_name_for_my_variable;
    cout << Val << endl;
    Val++;
    cout << Val << endl;
}

void pointers_array() {
    int arr[]{ 8, 11, 2, 7, 9 };
    int* px = arr;
    int* py = &(arr[3]);

    int& my_fav = arr[0];
    cout << *px << " " << my_fav << " " << px << endl;

    cout << px << " " << py << endl;
    cout << px - py << endl;

    cout << px << " " << px + 1 << " " << *(px + 1) << endl;
}

void showarr_by_pointers() {
    int arr[]{ 1,2,3,5,7,9 };

    for (int k = 0; k < size(arr); k++) {
        cout << *(arr + k) << ", ";
    }
    cout << endl;




    for (int* pk = arr; pk != arr + size(arr); pk++) {
        cout << *pk << ", ";
    }
    cout << endl;
}


int main() {
    //task0();
    //pointers_array();
    showarr_by_pointers();
}