Character Set in C

In the C programming language, the character set refers to a set of all the valid characters that we can use in the source program for forming words, expressions, and numbers.

The source character set contains all the characters that we want to use for the source program text. On the other hand, the execution character set consists of the set of those characters that we might use during the execution of any program. Thus, it is not a prerequisite that the execution character set and the source character set will be the same, or they will match altogether.

In this article, we will take a closer look at the Character Set in C according to the GATE Syllabus for CSE (Computer Science Engineering). Read ahead to know more.

Table of Contents

• Use Of Character Set In C
• Types Of Characters In C
  • Alphabets
  • Digits
  • Special Characters
  • White Spaces
• Summary Of Special Characters In C
• Purpose Of Character Set In C
  • Ascii Values
    • Control Characters
    • Printable Characters
    • Character Equivalence
• Practice Problems On Character Set In C
• FAQs

Use of Character Set in C

Just like we use a set of various words, numbers, statements, etc., in any language for communication, the C programming language also consists of a set of various different types of characters. These are known as the characters in C. They include digits, alphabets, special symbols, etc. The C language provides support for about 256 characters.

Every program that we draft for the C program consists of various statements. We use words for constructing these statements. Meanwhile, we use characters for constructing these statements. These characters must be from the C language character set. Let us look at the set of characters offered by the C language.

Types of Characters in C

The C programming language provides support for the following types of characters. In other words, these are the valid characters that we can use in the C language:

• Digits
• Alphabets
• Main Characters

All of these serve a different set of purposes, and we use them in different contexts in the C language.

Alphabets

The C programming language provides support for all the alphabets that we use in the English language. Thus, in simpler words, a C program would easily support a total of 52 different characters- 26 uppercase and 26 lowercase.

Digits

The C programming language provides the support for all the digits that help in constructing/ supporting the numeric values or expressions in a program. These range from 0 to 9, and also help in defining an identifier. Thus, the C language supports a total of 10 digits for constructing the numeric values or expressions in any program.

Special Characters

We use some special characters in the C language for some special purposes, such as logical operations, mathematical operations, checking of conditions, backspaces, white spaces, etc.

We can also use these characters for defining the identifiers in a much better way. For instance, we use underscores for constructing a longer name for a variable, etc.

The C programming language provides support for the following types of special characters:

White Spaces

The white spaces in the C programming language contain the following:

• Blank Spaces
• Carriage Return
• Tab
• New Line

Summary of Special Characters in C

Here is a table that represents all the types of character sets that we can use in the C language:

Purpose of Character Set in C

The character sets help in defining the valid characters that we can use in the source program or can interpret during the running of the program. For the source text, we have the source character set, while we have the execution character set that we use during the execution of any program.

But we have various types of character sets. For instance, one of the character sets follows the basis of the ASCII character definitions, while the other set consists of various kanji characters (Japanese).

The type of character set we use will have no impact on the compiler- but we must know that every character has different, unique values. The C language treats every character with different integer values. Let us know a bit more about the ASCII characters.

ASCII Values

All the character sets used in the C language have their equivalent ASCII value. The ASCII value stands for American Standard Code for Information Interchange value. It consists of less than 256 characters, and we can represent these in 8 bits or even less. But we use a special type for accommodating and representing the larger sets of characters. These are called the wide-character type or wchat_t.

However, a majority of the ANSI-compatible compilers in C accept these ASCII characters for both the character sets- the source and the execution. Every ASCII character will correspond to a specific numeric value.

Here is a list of all the ASCII characters, along with their assigned numeric values.

Control Characters

Printable Characters

(DEL is also a control character.)

Character Equivalence

Here are all the character sets in ASCII. The table below displays all the character’s hexadecimal, decimal, and octal values:

Practice Problems on Character Set in C

1. Which of these is a type of character set used in the C language?

A. Digits

B. Alphabets Characters

D. All of the above

Answer – D. All of the above

2. What types of alphabets does the language support?

A. Lowercase Alphabets and Characters

B. Uppercase Alphabets and Characters

C. All of the above

Answer – C. All of the above

3. How many characters does the C programming language support in total?

A. 52

B. 26

C. 256

D. 86

Answer – C. 256

4. How many digits do the C programming language support as character sets?

A. Nine

B. Eight

C. Five

D. Ten

Answer – D. Ten

Keep learning and stay tuned to get the latest updates on GATE Exam along with GATE Eligibility Criteria, GATE 2023, GATE Admit Card, GATE Syllabus for CSE (Computer Science Engineering), GATE CSE Notes, GATE CSE Question Paper, and more.

Also Explore,

• Arithmetic Operators in C
• Bitwise Operators in C
• Increment and The Base of Number SystemThe Base of Number SystemDecrement Operators in C
• Logical Operators in C