{"id":34,"date":"2019-04-12T22:47:27","date_gmt":"2019-04-12T22:47:27","guid":{"rendered":"https:\/\/www.kindsonthegenius.com\/cplusplus\/?p=34"},"modified":"2019-04-12T22:47:27","modified_gmt":"2019-04-12T22:47:27","slug":"c-data-types","status":"publish","type":"post","link":"https:\/\/www.kindsonthegenius.com\/cplusplus\/c-data-types\/","title":{"rendered":"C++ Data Types"},"content":{"rendered":"

We would cover C++ Data Types in this lesson under the following topics:<\/p>\n

    \n
  1. Introduction to C++ Data Types<\/a><\/li>\n
  2. C++ Built-in Data Types<\/a><\/li>\n
  3. Why do we need Data Types<\/a><\/li>\n
  4. The typedef Keyword<\/a><\/li>\n
  5. The enum Types<\/a><\/li>\n<\/ol>\n

     <\/p>\n

    1. Introduction to C++ Data Types<\/strong><\/h4>\n

    Data types is quite easy understand but very important. For example, a digit is different from a letter. And so on.<\/p>\n

    Also, remember that C++ is a strongly typed language. So you need to be aware of the data types available.<\/p>\n

    Just to remind you, in\u00a0 a strongly typed language, you must specify the data type of your variables.<\/p>\n

    We discuss more on variables in the next chapter.<\/p>\n

     <\/p>\n

     <\/p>\n

    2. C++ Built-in Data Types<\/strong><\/h4>\n

    Built-in data types are also called basic data types. C++ provide a number of data types which are listed in the table below:<\/p>\n\n\n\n\n\n\n\n\n\n\n
    Data Type<\/th>\nKeyword<\/th>\n<\/tr>\n
    Boolean<\/td>\nbool<\/td>\n<\/tr>\n
    Character<\/td>\nchar<\/td>\n<\/tr>\n
    Integer<\/td>\nint<\/td>\n<\/tr>\n
    Floating point<\/td>\nfloat<\/td>\n<\/tr>\n
    Double floating point<\/td>\ndouble<\/td>\n<\/tr>\n
    Valueless<\/td>\nvoid<\/td>\n<\/tr>\n
    Wide character<\/td>\nwchar_t<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

     <\/p>\n

    Some of these primitive data types can be modified using any of the modifiers listed below:<\/p>\n

      \n
    • short<\/li>\n
    • long<\/li>\n
    • signed<\/li>\n
    • unsigned<\/li>\n<\/ul>\n

       <\/p>\n

      3. Why do we need data types?<\/strong><\/h4>\n

      Data types are needed to indicate how much memory is reserved for the data. You can find in the table below, each data type along with the size and range.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
      Data Type<\/th>\nWidth in bytes<\/th>\nData Range<\/th>\n<\/tr>\n
      char<\/td>\n1 byte<\/td>\n-127 to 127 or 0 to 255<\/td>\n<\/tr>\n
      unsigned char<\/td>\n1 byte<\/td>\n0 to 255<\/td>\n<\/tr>\n
      signed char<\/td>\n1 byte<\/td>\n-127 to 127<\/td>\n<\/tr>\n
      int<\/td>\n4 bytes<\/td>\n-2147483648 to 2147483647<\/td>\n<\/tr>\n
      unsigned int<\/td>\n4 bytes<\/td>\n0 to 4294967295<\/td>\n<\/tr>\n
      signed int<\/td>\n4 bytes<\/td>\n-2147483648 to 2147483647<\/td>\n<\/tr>\n
      short int<\/td>\n2 bytes<\/td>\n-32768 to 32767<\/td>\n<\/tr>\n
      unsigned short int<\/td>\n<\/td>\n0 to 65,535<\/td>\n<\/tr>\n
      signed short int<\/td>\n<\/td>\n-32768 to 32767<\/td>\n<\/tr>\n
      long int<\/td>\n4 bytes<\/td>\n-2,147,483,648 to 2,147,483,647<\/td>\n<\/tr>\n
      signed long int<\/td>\n4 bytes<\/td>\nsame as long int<\/td>\n<\/tr>\n
      unsigned long int<\/td>\n4 bytes<\/td>\n0 to 4,294,967,295<\/td>\n<\/tr>\n
      float<\/td>\n4 bytes<\/td>\n+\/- 3.4e +\/- 38 (~7 digits)<\/td>\n<\/tr>\n
      double<\/td>\n8 bytes<\/td>\n+\/- 1.7e +\/- 308 (~15 digits)<\/td>\n<\/tr>\n
      long double<\/td>\n8 bytes<\/td>\n+\/- 1.7e +\/- 308 (~15 digits)<\/td>\n<\/tr>\n
      wchar_t<\/td>\n2 or 4 bytes<\/td>\n1 wide character<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

       <\/p>\n

      But sometimes, the actual size of the may vary depending on the computer or compiler being used.<\/p>\n

      You can find out the size of each data type using the sizeof(datatype). The code below prints out the sizes of different variables.<\/p>\n

       <\/p>\n

      \/\/ Program to display size of data types<\/span>\r\n\/\/ By Kindson The Genius<\/span>\r\n#include <iostream><\/span>\r\nusing<\/span> namespace<\/span> std;\r\n\r\nint<\/span> main<\/span>() {\r\n   cout <<<\/span> \"Size of int: \"<\/span> <<<\/span> sizeof<\/span>(int<\/span>) <<<\/span> endl;\r\n   cout <<<\/span> \"Size of char: \"<\/span> <<<\/span> sizeof<\/span>(char<\/span>) <<<\/span> endl;\r\n   cout <<<\/span> \"Size of short int: \"<\/span> <<<\/span> sizeof<\/span>(short<\/span> int<\/span>) <<<\/span> endl;\r\n   cout <<<\/span> \"Size of long int: \"<\/span> <<<\/span> sizeof<\/span>(long<\/span> int<\/span>) <<<\/span> endl;\r\n   cout <<<\/span> \"Size of float: \"<\/span> <<<\/span> sizeof<\/span>(float<\/span>) <<<\/span> endl;\r\n   cout <<<\/span> \"Size of double: \"<\/span> <<<\/span> sizeof<\/span>(double<\/span>) <<<\/span> endl;\r\n   cout <<<\/span> \"Size of wchar_t: \"<\/span> <<<\/span> sizeof<\/span>(wchar_t<\/span>) <<<\/span> endl;\r\n   \r\n   return<\/span> 0<\/span>;\r\n}\r\n<\/pre>\n
       <\/p>\n
      In this code, the <<endl is used to add a new line after each data type printed.<\/p>\n
      This code will give an output below:<\/p>\n
       <\/p>\n
      Size of int<\/span> :<\/span> 4<\/span>\r\nSize of char<\/span> :<\/span> 1<\/span>\r\nSize of short<\/span> int<\/span> :<\/span> 2<\/span>\r\nSize of long<\/span> int<\/span> :<\/span> 4<\/span>\r\nSize of float<\/span> :<\/span> 4<\/span>\r\nSize of double<\/span> :<\/span> 8<\/span>\r\nSize of wchar_t<\/span> :<\/span> 4<\/span>\r\n<\/pre>\n
       <\/p>\n
       <\/p>\n
      4. The typedef Keyword<\/strong><\/h4>\n
      Interestingly, you can change the name of the data types. C++ allows you to do that using the typedef keyword.<\/p>\n
      The syntax is:<\/p>\n
      typedef<\/span> type newname;\r\n<\/pre>\n
       <\/p>\n
      I don’t thing you’ll use this much. So don’t bother much but just know the syntax.<\/p>\n
       <\/p>\n
       <\/p>\n
      5. enum Types (or Enumerated types)<\/strong><\/h4>\n
      This is a way to provide a type name for a set of items. For example, you have a list of fruits, say, orange, banana, apple, pear. We want to give them a type called fruit. The we can achieve this using the syntax below:<\/p>\n
       <\/p>\n
      enum<\/span> fruit {orange, banana, apple, pear};\r\n\r\nfruit f;\r\n\r\nf =<\/span> banana;\r\n<\/pre>\n
       <\/p>\n
      In this case, fruit is an enum type<\/p>\n
      Now about enum types. The list of items inside the braces have default values starting from 0. Therefore the value of orange is 0, the value of banana is 1 and so on.<\/p>\n","protected":false},"excerpt":{"rendered":"
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