Задачи с массивами

#include <iostream>
#include <algorithm>
 
using std::cout;
 
void func(void* src, int sz, unsigned char val)
{
   unsigned char *ptr = static_cast<unsigned char *>(src);
   for(int i = 0; i < sz; ++i)
   {
      ptr[i] = val;
   }
}
 
void print(int &val)
{
   cout<<val<<", ";
}
 
int main()
{
   const size_t szArray = 10;
   int mas[szArray];
   cout<<"Before execution of func\n";
   std::for_each(mas, mas + szArray, print); //всякий мусор
   func(mas, sizeof(int) * szArray , 0);
   cout<<"\nAfter execution of func\n";
   std::for_each(mas, mas + szArray, print); //нули
   return 0;
}

#include <iostream>
#include <algorithm>
 
using std::cout;
 
 
void print(double val)
{
   cout<<val<<", ";
}
 
int main()
{
   const double constArray[] = {1.1, 2.2, 3.3};
   volatile double volatileArray[] = {10.1, 20.2, 30.3};
   cout<<"constArray before changes\n";
   std::for_each(constArray, constArray + 3, print);
   cout<<"\nvolatileArray before changes\n";
   std::for_each(volatileArray, volatileArray + 3, print);
   for(int i = 0; i < 3; ++i)
   {
      double * ptr = const_cast<double*>(constArray + i);
      *ptr = 0;
      volatileArray[i] = 0;
   }
   cout<<"\nconstArray after changesn";
   std::for_each(constArray, constArray + 3, print);
   cout<<"\nvolatileArray after trying to change\n";
   std::for_each(volatileArray, volatileArray + 3, print);   
   return 0;
}

void func(void* p, int size, int n)
{
    for (int i = 0; i<size; i++)
        static_cast<int*>(p)[i] = n;
}
int main()
{
    int arr[] = {1,2,3,4,5};
    void* parr = static_cast<void*>(arr);
    func(parr, sizeof arr/sizeof (int), 10);
    for (int i = 0; i<sizeof arr/sizeof (int); i++)
        cout<<static_cast<int*>(parr)[i]<<" ";
    cout<<endl;
    system("pause");
    return 0;
}