Step by Step solution about How to resolve the algorithm Variable size/Get step by step in the C++ programming language

1. sizeof:

In C++, sizeof is a unary operator that returns the size of the operand in bytes.

• std::size_t intsize = sizeof(int);: This line gets the size of an int data type in bytes and stores it in a variable named intsize.

• std::size_t intbits = CHAR_BITS*sizeof(int);: This line gets the number of bits in an int data type, which is CHAR_BITS (usually 8) multiplied by the size of int in bytes. It stores the result in intbits.

2. sizeof(variable):

• std::size_t a_size = sizeof a;: This line gets the size of the variable a, which is an integer, and stores it in a_size. It's useful when you need to pass the size of an array or structure to a function.

3. sizeof(expression):

• std::size_t size = sizeof (3*6 + 7.5);: This line calculates the size of an expression (3*6 + 7.5), which is the size of the result type, which is a double in this case (8 bytes on most platforms). It stores the result in size.

#include <cstdlib>
std::size_t intsize = sizeof(int);


#include <climits>
#include <cstdlib>
std::size_t intbits = CHAR_BITS*sizeof(int);


#include <cstdlib>
int a = 1;
std::size_t a_size = sizeof a;


#include <cstdlib>
std::size_t size = sizeof (3*6 + 7.5);