All variables use data-type during declaration to restrict the type of data to be stored. Therefore, we can say that data types are used to tell the variables the type of data it can store. Whenever a variable is defined in C++, the compiler allocates some memory for that variable based on the data type with which it is declared. Every data type requires a different amount of memory. Show C++ supports a wide variety of data types and the programmer can select the data type appropriate to the needs of the application. Data types specify the size and types of value to be stored. However, storage representation and machine instructions to manipulate each data type differ from machine to machine, although C++ instructions are identical on all machines. C++ supports the following data types:
Data types in C++ are mainly divided into three types: 1. Primitive Data Types: These data types are built-in or predefined data types and can be used directly by the user to declare variables. example: int, char, float, bool, etc. Primitive data types available in C++ are:
2. Derived Data Types: The data types that are derived from the primitive or built-in datatypes are referred to as Derived Data Types. These can be of four types namely:
3. Abstract or User-Defined Data Types: These data types are defined by the user itself. Like, as defining a class in C++ or a structure. C++ provides the following user-defined datatypes:
This article discusses primitive data types available in C++.
The size of variables might be different from those shown in the above table, depending on
the compiler sizeof operator — sizeof operator is used to find the number of bytes occupied by a variable/data type in computer memory. Eg: int m , x[50]; cout<<sizeof(m); //returns 4 which is the number of bytes occupied by the integer variable “m”. cout<<sizeof(x); //returns 200 which is the number of bytes occupied by the integer array variable “x”. C++
Output Size of char : 1 Size of int : 4 Size of long : 8 Size of float : 4 Size of double : 8 Time Complexity: O(1)Space Complexity: O(1)Datatype ModifiersAs the name suggests, datatype modifiers are used with the built-in data types to modify the length of data that a particular data type can hold. Data type modifiers available in C++ are:
The below table summarizes the modified size and range of built-in datatypes when combined with the type modifiers:
Note: Above values may vary from compiler to compiler. In the above example, we have considered GCC 32 bit. Now to get the range of data types refer to the following chart Note: syntax<limits.h> header file is defined to find the range of fundamental data-types. Unsigned modifiers have minimum value is zero. So, no macro constants are defined for the unsigned minimum value. Macro Constants Name
Expresses The actual value depends on the particular system and library implementation but shall reflect the limits of these types in the target platform. LLONG_MIN, LLONG_MAX, and ULLONG_MAX are defined for libraries complying with the C standard of 1999 or later (which only includes the C++ standard since 2011: C++11). C++ Program to Find the Range of Data Types using Macro Constants CPP
Output: Size of char : 1 byte Size of int : 4 bytes Size of short int : 2 bytes Size of long int : 8 bytes Size of signed long int : 8 bytes Size of unsigned long int : 8 bytes Size of float : 4 bytes Size of double : 8 bytes Size of wchar_t : 4 bytes Time Complexity: O(1) Space Complexity: O(1) This article is contributed by Harsh Agarwal. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to . See your article appearing on the GeeksforGeeks main page and help other Geeks. Please write comments if you find anything incorrect, or if you want to share more information about the topic discussed above. Which data type requires the least amount of memory?byte datatype has a range from -128 to 127 and it requires very little memory (only 1 byte).
How data types are stored in memory?Each individual data value in a data set is usually stored using one or more bytes of memory, but at the lowest level, any data stored on a computer is just a large collection of bits. For example, the first 256 bits (32 bytes) of the electronic format of this book are shown below.
Can a boolean variable hold any character?A Boolean variable can hold any character. FALSE; Boolean is a data type used in java to store the value of true or false only. If the results are true it stores 1 as true, and 0 if it is false.
What is the range of values that a short data type can support?short: The short data type is a 16-bit signed two's complement integer. It has a minimum value of -32,768 and a maximum value of 32,767 (inclusive).
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