解释C语言中的C标记符

Tokens are generally smallest, indivisible units in a C program with different meanings.

Types of Tokens

The various types of tokens in C are as follows −

• Identifiers − This refers to the name of the functions, variables, arrays, structures, etc.

• Operators − These are the symbols that tells to the C compiler to perform some logical, mathematical, or relational operations.

• Special Characters − All characters except alphabets and digits are called special characters.

• Constants − Some fixed values that cannot be changed during the program execution are known as constant terms

• Keywords/Reserved Names − These are Predefined words with some special meanings that cannot be used as variable names.

Example

Following is the C program for usage of tokens −

#include<stdio.h>
int main(){
   int p, q, result;
   p = 2, q= 3;
   result = p + q;
   printf ("result = %d 
", result);
}

这里，

• main是标识符。
• {,}, (,)是分隔符。
• int是关键字。
• p,q,result是标识符。
• main, {, }, (, ), int, p, q, result一起被称为标记。