C++ sizeof operator

C++ Operators

sizeofis a keyword, it is a compile-time operator used to determine the byte size of a variable or data type.

The sizeof operator can be used to obtain the size of classes, structures, unions, and other user-defined data types.

The syntax for using sizeof is as follows:

sizeof (data type)

Here, data type is the data type whose size is to be calculated, including classes, structures, unions, and other user-defined data types.

Please try the following example to understand the usage of sizeof in C++. Copy and paste the following C++ program into the test.cpp file, compile and run the program.

#include <iostream>
using namespace std;
 
int main()
{
   cout << "Size of char : " << sizeof(char) << endl;
   cout << "Size of int : " << sizeof(int) << endl;
   cout << "Size of short int : " << sizeof(short int) << endl;
   cout << "Size of long int : " << sizeof(long int) << endl;
   cout << "Size of float : " << sizeof(float) << endl;
   cout << "Size of double : " << sizeof(double) << endl;
   cout << "Size of wchar_t : " << sizeof(wchar_t) << endl;
   return 0;
}

When the above code is compiled and executed, it produces the following results, which may vary depending on the machine used.

Size of char : 1
Size of int : 4
Size of short int : 2
Size of long int : 4
Size of float : 4
Size of double : 8
Size of wchar_t : 4

C++ Operators

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