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Normal variable and pointer

kakaducsy (39)
Can you explain about bellow code?Why (na+1)=0x4? when a variable store stack or heap ?

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  // Example program
#include <iostream>
#include <string>

int main()
{
  int *name= new int;
  std::cout << "Address, " << &name << "\n";
  std::cout << "    Value, " << name << "\n\n";
  int nam;
  std::cout << "Address, " << &nam << "\n";
  std::cout << "    Value, " << (nam+1) << "\n\n";
  int *na;
  std::cout << "Address, " << &na << "\n";
  std::cout << "    Value, " << (na+1) << "\n";
}



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Address, 0x72b975e06c60
    Value, 0xda5750

Address, 0x72b975e06c5c
    Value, 1

Address, 0x72b975e06c68
    Value, 0x4
Last edited on
dutch (2548)
It's just an arbitrary value since you never initialized it. Try this:
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#include <iostream>

int main()
{
  int *a = new int;
  *a = 123;
  std::cout << "Address: " << &a << "\n";
  std::cout << "  Value: " <<  a << "\n";
  std::cout << " *Value: " << *a << "\n\n";
  int b = 234;
  std::cout << "Address: " << &b << "\n";
  std::cout << "  Value: " <<  b << "\n\n";
  int *c = &b;
  std::cout << "Address: " << &c << "\n";
  std::cout << "  Value: " <<  c << "\n";
  std::cout << " *Value: " << *c << "\n";
}

Address: 0x78b000607b60
  Value: 0x27f6e40
 *Value: 123

Address: 0x78b000607b5c
  Value: 234

Address: 0x78b000607b68
  Value: 0x78b000607b5c
 *Value: 234
Last edited on
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