Understand the types of five basic data type constants

To understand the five types of basic data type constants, you need specific code examples

In computer programming, constants refer to values ​​that are fixed in the program. Basic data type constants refer to the most basic data type constants used in programming languages. Common basic data types include integer types, floating point types, character types, Boolean types and null types. The following will introduce these five basic data type constants in detail and provide specific code examples.

1. Integer type constant
   Integer type constant is a constant used to represent an integer. In most programming languages, integer type constants can represent positive integers, negative integers, and zero. Common integer types include integer (int), long integer (long) and short integer (short).

Code example:

int num1 = 100;  // 整数类型常量
long num2 = 10000000000L;  // 长整数类型常量
short num3 = -10;  // 短整数类型常量

2. Floating point type constant
   Floating point type constant is used to represent a numerical value with a decimal point. Common floating-point types include single-precision floating-point (float) and double-precision floating-point (double).

Code example:

float num1 = 3.14f;  // 单精度浮点数类型常量
double num2 = 3.1415926;  // 双精度浮点数类型常量

3. Character type constants
   Character type constants are used to represent a single character. In most programming languages, character type constants are enclosed in single quotes (').

Code example:

char ch1 = 'A';  // 字符类型常量
char ch2 = '中';  // 字符类型常量（表示中文字符）

4. Boolean type constant
   Boolean type constant is used to represent a true or false value. In most programming languages, Boolean constants have only two values: true and false.

Code example:

boolean bool1 = true;  // 布尔类型常量
boolean bool2 = false;  // 布尔类型常量

5. Empty type constant
   Empty type constant represents an uncertain value or missing value. In most programming languages, you can use the keyword null to represent an empty type constant.

Code sample:

String str = null;  // 空类型常量

Through the above code sample, we can better understand the five types of basic data type constants. No matter which programming language you are in, these five types of constants will be included, and the uses of constants are very wide. Being familiar with and understanding the types and usage of these constants will help us write more efficient and accurate programs.

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