What is Size of int variable in c?

Answer 1

The size of an int variable in c is a function of the compiler implementation. It is usually a word in the underlying computer architecture. Original Microsoft C/C++ compilers for the 16 bit platform defined an int as 2 bytes. Current compilers for the 32 bit platform define an int as 4 bytes. The current ANSI C standard provides that an int is at least 4 bytes, but it could be higher, say 8 bytes on a 64 bit platform.

Answer 2

It depends what you mean by size. The std::string::size() member function will tell you the length of a string in chars up to but not including the null-terminator, while std::string::capacity() will tell you the maximum number of characters (excluding the null-terminator) the string will accommodate before a resize occurs. However, size could also refer to the std::string object itself, and that can be obtained via sizeof (std::string).

Or perhaps you wish to know the total memory consumed by your variable? For a string, T, of type char, the total memory consumed should be sizeof (T) + T.capacity() + sizeof (char). However, many implementations make use of the short string optimisation (SSO) to store short strings inside the object itself rather than on the free store, but this optimisation is implementation defined (it is not defined by the standard). 16 characters (including the null-terminator) is not unusual for SSO, but it's by no means universal.

If memory consumption is a concern, the most reliable method of keeping track of consumption is to implement your own string class. If you need to monitor an existing class's consumption, you'll need to override the global operator new and provide your own memory manager (not for the feint of heart).

Answer 3

One byte.