dynamiczna alokacja pamieci - zadania

ZADANIE 1

#include <iostream>

using namespace std;
int a;

int main(){
cout << "podaj liczbe elementow tablicy: ";
cin >> a;
int *tab = new int[a];
for (int i = 0; i < a; i++) cout << (intptr_t)&tab[i] << endl;
delete []tab;
}

ZADANIE 2

#include <iostream>

using namespace std;
int a;
float suma;

int main(){
cout << "podaj liczbe ocen: ";
cin >> a;
int *tab = new int[a];
for (int i = 0; i < a; i++){
    cout << "podaj ocene: " << endl;
    cin >> tab[i];
}
for (int i = 0; i < a; i++) suma += tab[i];
float srednia = suma/a;
cout << "Twoja srednia wynosi: " << srednia << endl;
if (srednia > 1.76) cout << "przechodzisz do nastepnej klasy"<< endl;
else cout << "nie przechodzisz do nastepnej klasy" << endl;
delete []tab;
}

ZADANIE 3

#include <iostream>

using namespace std;
int a;

int main(){
cout << "podaj ile wyrazow ciagu chcesz podac: ";
cin >> a;
int *tab = new int[a];
tab[0] = 1;
cout << tab[0] << endl;
tab[1] = 1;
cout << tab[1] << endl;
for (int i = 2; i < a; i++){
    tab[i] = tab[i-1] + tab[i-2];
    cout << tab[i] << endl;
}
delete []tab;
}