Dev - C++ - Duda extraña con punteros

#include <iostream>

int main()

{

   int numero=4;

   int *ptr;

   ptr= №

   std::cout  << ptr << std::endl;

   return 0;

}

#include <iostream>

int main()

{

   char letra='X';

   char *ptr;

   ptr= &letra;

   std::cout  << ptr << std::endl;

   return 0;

}

#include <iostream>

int main() {

    char letra = 'X';

    char *ptr = NULL;

    ptr = &letra;

    std::cout << ptr[0] << std::endl;

    return 0;

}

#include <iostream>

using namespace std;

int main() {

    char *ptr = "abc";

    std::cout << ptr[0] << ptr[1] << ptr[2];

    return 0;

}

std::cout << ptr << std::endl;

00415345  mov         esi,esp

00415347  mov         eax,dword ptr [MSVCP100D_NULL_THUNK_DATA (42D334h)]

0041534C  push        eax

0041534D  mov         edi,esp

0041534F  mov         ecx,dword ptr [ebp-18h]

00415352  push        ecx

00415353  mov         ecx,dword ptr [__imp_std::cout (42D324h)]

00415359  call        dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (42D338h)]

0041535F  cmp         edi,esp

00415361  call        @ILT+430(__RTC_CheckEsp) (4111B3h)

00415366  mov         ecx,eax

00415368  call        dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (42D33Ch)]

0041536E  cmp         esi,esp

00415370  call        @ILT+430(__RTC_CheckEsp) (4111B3h)

     std::cout << ptr2 << std::endl;

00415375  mov         esi,esp

00415377  mov         eax,dword ptr [MSVCP100D_NULL_THUNK_DATA (42D334h)]

0041537C  push        eax

0041537D  mov         ecx,dword ptr [ebp-30h]

00415380  push        ecx

00415381  mov         edx,dword ptr [__imp_std::cout (42D324h)]

00415387  push        edx

00415388  call        std::operator<<<std::char_traits<char> > (411320h)

0041538D  mov         ecx,eax

0041538F  call        dword ptr [__imp_std::basic_ostream<char,std::char_traits<char> >::operator<< (42D33Ch)]

00415395  cmp         esi,esp

00415397  call        @ILT+430(__RTC_CheckEsp) (4111B3h)

ostream& operator<< (void* val);

ostream& operator<< (ostream& os, const char* s);

std::cout  << static_cast<void*>(ptr) << std::endl;