Data Types in C++

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When you create a variable, you reserve some space in memory.

Different data types take up different amount of space.


Some of the fundamental data types in C++ are :

source : https://www.tutorialspoint.com/cplusplus/cpp_data_types.htm


Calculation for range of int :

1 int contains 4 bytes and 1 byte contains 8 bits
So, 1 int contains = 4x8 = 32 bits
n bits can have 2^n patterns
So, 32 bits have 2^32 = 4294967296, which is the range of unsigned int.

Size of data types can also vary by machine.


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