assignment character in c

C String – How to Declare Strings in the C Programming Language

Computers store and process all kinds of data.

Strings are just one of the many forms in which information is presented and gets processed by computers.

Strings in the C programming language work differently than in other modern programming languages.

In this article, you'll learn how to declare strings in C.

Before doing so, you'll go through a basic overview of what data types, variables, and arrays are in C. This way, you'll understand how these are all connected to one another when it comes to working with strings in C.

Knowing the basics of those concepts will then help you better understand how to declare and work with strings in C.

Let's get started!

Data types in C

C has a few built-in data types.

They are int , short , long , float , double , long double and char .

As you see, there is no built-in string or str (short for string) data type.

The char data type in C

From those types you just saw, the only way to use and present characters in C is by using the char data type.

Using char , you are able to to represent a single character – out of the 256 that your computer recognises. It is most commonly used to represent the characters from the ASCII chart.

The single characters are surrounded by single quotation marks .

The examples below are all char s – even a number surrounded by single quoation marks and a single space is a char in C:

Every single letter, symbol, number and space surrounded by single quotation marks is a single piece of character data in C.

What if you want to present more than one single character?

The following is not a valid char – despite being surrounded by single quotation marks. This is because it doesn't include only a single character inside the single quotation marks:

'freeCodeCamp is awesome'

When many single characters are strung together in a group, like the sentence you see above, a string is created. In that case, when you are using strings, instead of single quotation marks you should only use double quotation marks.

"freeCodeCamp is awesome"

How to declare variables in C

So far you've seen how text is presented in C.

What happens, though, if you want to store text somewhere? After all, computers are really good at saving information to memory for later retrieval and use.

The way you store data in C, and in most programming languages, is in variables.

Essentially, you can think of variables as boxes that hold a value which can change throughout the life of a program. Variables allocate space in the computer's memory and let C know that you want some space reserved.

C is a statically typed language, meaning that when you create a variable you have to specify what data type that variable will be.

There are many different variable types in C, since there are many different kinds of data.

Every variable has an associated data type.

When you create a variable, you first mention the type of the variable (wether it will hold integer, float, char or any other data values), its name, and then optionally, assign it a value:

Be careful not to mix data types when working with variables in C, as that will cause errors.

For intance, if you try to change the example from above to use double quotation marks (remember that chars only use single quotation marks), you'll get an error when you compile the code:

As mentioned earlier on, C doesn't have a built-in string data type. That also means that C doesn't have string variables!

How to create arrays in C

An array is essentially a variable that stores multiple values. It's a collection of many items of the same type.

As with regular variables, there are many different types of arrays because arrays can hold only items of the same data type. There are arrays that hold only int s, only float s, and so on.

This is how you define an array of ints s for example:

First you specify the data type of the items the array will hold. Then you give it a name and immediately after the name you also include a pair of square brackets with an integer. The integer number speficies the length of the array.

In the example above, the array can hold 3 values.

After defining the array, you can assign values individually, with square bracket notation, using indexing. Indexing in C (and most programming languages) starts at 0 .

You reference and fetch an item from an array by using the name of the array and the item's index in square brackets, like so:

What are character arrays in C?

So, how does everything mentioned so far fit together, and what does it have to do with initializing strings in C and saving them to memory?

Well, strings in C are actually a type of array – specifically, they are a character array . Strings are a collection of char values.

How strings work in C

In C, all strings end in a 0 . That 0 lets C know where a string ends.

That string-terminating zero is called a string terminator . You may also see the term null zero used for this, which has the same meaning.

Don't confuse this final zero with the numeric integer 0 or even the character '0' - they are not the same thing.

The string terminator is added automatically at the end of each string in C. But it is not visible to us – it's just always there.

The string terminator is represented like this: '\0' . What sets it apart from the character '0' is the backslash it has.

When working with strings in C, it's helpful to picture them always ending in null zero and having that extra byte at the end.

Each character takes up one byte in memory.

The string "hello" , in the picture above, takes up 6 bytes .

"Hello" has five letters, each one taking up 1 byte of space, and then the null zero takes up one byte also.

The length of strings in C

The length of a string in C is just the number of characters in a word, without including the string terminator (despite it always being used to terminate strings).

The string terminator is not accounted for when you want to find the length of a string.

For example, the string freeCodeCamp has a length of 12 characters.

But when counting the length of a string, you must always count any blank spaces too.

For example, the string I code has a length of 6 characters. I is 1 character, code has 4 characters, and then there is 1 blank space.

So the length of a string is not the same number as the number of bytes that it has and the amount of memory space it takes up.

How to create character arrays and initialize strings in C

The first step is to use the char data type. This lets C know that you want to create an array that will hold characters.

Then you give the array a name, and immediatelly after that you include a pair of opening and closing square brackets.

Inside the square brackets you'll include an integer. This integer will be the largest number of characters you want your string to be including the string terminator.

You can initialise a string one character at a time like so:

But this is quite time-consuming. Instead, when you first define the character array, you have the option to assign it a value directly using a string literal in double quotes:

If you want, istead of including the number in the square brackets, you can only assign the character array a value.

It works exactly the same as the example above. It will count the number of characters in the value you provide and automatically add the null zero character at the end:

Remember, you always need to reserve enough space for the longest string you want to include plus the string terminator.

If you want more room, need more memory, and plan on changing the value later on, include a larger number in the square brackets:

How to change the contents of a character array

So, you know how to initialize strings in C. What if you want to change that string though?

You cannot simply use the assignment operator ( = ) and assign it a new value. You can only do that when you first define the character array.

As seen earlier on, the way to access an item from an array is by referencing the array's name and the item's index number.

So to change a string, you can change each character individually, one by one:

That method is quite cumbersome, time-consuming, and error-prone, though. It definitely is not the preferred way.

You can instead use the strcpy() function, which stands for string copy .

To use this function, you have to include the #include <string.h> line after the #include <stdio.h> line at the top of your file.

The <string.h> file offers the strcpy() function.

When using strcpy() , you first include the name of the character array and then the new value you want to assign. The strcpy() function automatically add the string terminator on the new string that is created:

And there you have it. Now you know how to declare strings in C.

To summarize:

• C does not have a built-in string function.
• To work with strings, you have to use character arrays.
• When creating character arrays, leave enough space for the longest string you'll want to store plus account for the string terminator that is included at the end of each string in C.
• Define the array and then assign each individual character element one at a time.
• OR define the array and initialize a value at the same time.
• When changing the value of the string, you can use the strcpy() function after you've included the <string.h> header file.

If you want to learn more about C, I've written a guide for beginners taking their first steps in the language.

It is based on the first couple of weeks of CS50's Introduction to Computer Science course and I explain some fundamental concepts and go over how the language works at a high level.

You can also watch the C Programming Tutorial for Beginners on freeCodeCamp's YouTube channel.

Thanks for reading and happy learning :)

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How to Declare and Use Character Variables in C Programming

C basic concepts.

In this lesson, we will discover how to declare and use character variables in C programming with this practical guide. Get hands-on with examples and take a quiz to reinforce your understanding.

What is Character Variable

In C programming, a character variable can hold a single character enclosed within single quotes. To declare a variable of this type, we use the keyword char , which is pronounced as kar . With a char variable, we can store any character, including letters, numbers, and symbols.

Syntax of Declaring Character Variable in C

Here char is used for declaring Character data type and variable_name is the name of variable (you can use any name of your choice for example: a, b, c, alpha, etc.) and ; is used for line terminator (end of line).

Now let's see some examples for more understanding.

Declare a character variable x .

Declare 3 character variables x , y , and z to assign 3 different characters in it.

Note: A character can be anything, it can be an alphabet or digit or any other symbol, but it must be single in quantity.

Declare a character variable x and assign the character '$' and change it value to @ in the next line.

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cppreference.com

Assignment operators.

Assignment and compound assignment operators are binary operators that modify the variable to their left using the value to their right.

[ edit ] Simple assignment

The simple assignment operator expressions have the form

Assignment performs implicit conversion from the value of rhs to the type of lhs and then replaces the value in the object designated by lhs with the converted value of rhs .

Assignment also returns the same value as what was stored in lhs (so that expressions such as a = b = c are possible). The value category of the assignment operator is non-lvalue (so that expressions such as ( a = b ) = c are invalid).

rhs and lhs must satisfy one of the following:

• both lhs and rhs have compatible struct or union type, or..
• rhs must be implicitly convertible to lhs , which implies
• both lhs and rhs have arithmetic types , in which case lhs may be volatile -qualified or atomic (since C11)
• both lhs and rhs have pointer to compatible (ignoring qualifiers) types, or one of the pointers is a pointer to void, and the conversion would not add qualifiers to the pointed-to type. lhs may be volatile or restrict (since C99) -qualified or atomic (since C11) .
• lhs is a (possibly qualified or atomic (since C11) ) pointer and rhs is a null pointer constant such as NULL or a nullptr_t value (since C23)

[ edit ] Notes

If rhs and lhs overlap in memory (e.g. they are members of the same union), the behavior is undefined unless the overlap is exact and the types are compatible .

Although arrays are not assignable, an array wrapped in a struct is assignable to another object of the same (or compatible) struct type.

The side effect of updating lhs is sequenced after the value computations, but not the side effects of lhs and rhs themselves and the evaluations of the operands are, as usual, unsequenced relative to each other (so the expressions such as i = ++ i ; are undefined)

Assignment strips extra range and precision from floating-point expressions (see FLT_EVAL_METHOD ).

In C++, assignment operators are lvalue expressions, not so in C.

[ edit ] Compound assignment

The compound assignment operator expressions have the form

The expression lhs @= rhs is exactly the same as lhs = lhs @ ( rhs ) , except that lhs is evaluated only once.

[ edit ] References

• C17 standard (ISO/IEC 9899:2018):
• 6.5.16 Assignment operators (p: 72-73)
• C11 standard (ISO/IEC 9899:2011):
• 6.5.16 Assignment operators (p: 101-104)
• C99 standard (ISO/IEC 9899:1999):
• 6.5.16 Assignment operators (p: 91-93)
• C89/C90 standard (ISO/IEC 9899:1990):
• 3.3.16 Assignment operators

[ edit ] See Also

Operator precedence

[ edit ] See also

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Next: Execution Control Expressions , Previous: Arithmetic , Up: Top   [ Contents ][ Index ]

7 Assignment Expressions

As a general concept in programming, an assignment is a construct that stores a new value into a place where values can be stored—for instance, in a variable. Such places are called lvalues (see Lvalues ) because they are locations that hold a value.

An assignment in C is an expression because it has a value; we call it an assignment expression . A simple assignment looks like

We say it assigns the value of the expression value-to-store to the location lvalue , or that it stores value-to-store there. You can think of the “l” in “lvalue” as standing for “left,” since that’s what you put on the left side of the assignment operator.

However, that’s not the only way to use an lvalue, and not all lvalues can be assigned to. To use the lvalue in the left side of an assignment, it has to be modifiable . In C, that means it was not declared with the type qualifier const (see const ).

The value of the assignment expression is that of lvalue after the new value is stored in it. This means you can use an assignment inside other expressions. Assignment operators are right-associative so that

is equivalent to

This is the only useful way for them to associate; the other way,

would be invalid since an assignment expression such as x = y is not valid as an lvalue.

Warning: Write parentheses around an assignment if you nest it inside another expression, unless that is a conditional expression, or comma-separated series, or another assignment.

• How to Initialize Char Array in C

Use {} Curly Braced List Notation to Initialize a char Array in C

Use string assignment to initialize a char array in c, use {{ }} double curly braces to initialize 2d char array in c.

This article will demonstrate multiple methods of how to initialize a char array in C.

A char array is mostly declared as a fixed-sized structure and often initialized immediately. Curly braced list notation is one of the available methods to initialize the char array with constant values.

It’s possible to specify only the portion of the elements in the curly braces as the remainder of chars is implicitly initialized with a null byte value.

It can be useful if the char array needs to be printed as a character string. Since there’s a null byte character guaranteed to be stored at the end of valid characters, then the printf function can be efficiently utilized with the %s format string specifier to output the array’s content.

Another useful method to initialize a char array is to assign a string value in the declaration statement. The string literal should have fewer characters than the length of the array; otherwise, there will be only part of the string stored and no terminating null character at the end of the buffer.

Thus, if the user will try to print the array’s content with the %s specifier, it might access the memory region after the last character and probably will throw a fault.

Note that c_arr has a length of 21 characters and is initialized with a 20 char long string. As a result, the 21st character in the array is guaranteed to be \0 byte, making the contents a valid character string.

The curly braced list can also be utilized to initialize two-dimensional char arrays. In this case, we declare a 5x5 char array and include five braced strings inside the outer curly braces.

Note that each string literal in this example initializes the five-element rows of the matrix. The content of this two-dimensional array can’t be printed with %s specifier as the length of each row matches the length of the string literals; thus, there’s no terminating null byte stored implicitly during the initialization. Usually, the compiler will warn if the string literals are larger than the array rows.

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Related Article - C Array

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C Programming Tutorial

• Character Array and Character Pointer in C

Last updated on July 27, 2020

In this chapter, we will study the difference between character array and character pointer. Consider the following example:

Can you point out similarities or differences between them?

The similarity is:

The type of both the variables is a pointer to char or (char*) , so you can pass either of them to a function whose formal argument accepts an array of characters or a character pointer.

Here are the differences:

arr is an array of 12 characters. When compiler sees the statement:

On the other hand when the compiler sees the statement.

It allocates 12 consecutive bytes for string literal "Hello World" and 4 extra bytes for pointer variable ptr . And assigns the address of the string literal to ptr . So, in this case, a total of 16 bytes are allocated.

We already learned that name of the array is a constant pointer. So if arr points to the address 2000 , until the program ends it will always point to the address 2000 , we can't change its address. This means string assignment is not valid for strings defined as arrays.

On the contrary, ptr is a pointer variable of type char , so it can take any other address. As a result string, assignments are valid for pointers.

After the above assignment, ptr points to the address of "Yellow World" which is stored somewhere in the memory.

Obviously, the question arises so how do we assign a different string to arr ?

We can assign a new string to arr by using gets() , scanf() , strcpy() or by assigning characters one by one.

Recall that modifying a string literal causes undefined behavior, so the following operations are invalid.

Using an uninitialized pointer may also lead to undefined undefined behavior.

Here ptr is uninitialized an contains garbage value. So the following operations are invalid.

We can only use ptr only if it points to a valid memory location.

Now all the operations mentioned above are valid. Another way we can use ptr is by allocation memory dynamically using malloc() or calloc() functions.

Let's conclude this chapter by creating dynamic 1-d array of characters.

Expected Output:

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• Intro to C Programming
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Character Pointers and Functions in C

What is a character pointer in c.

A character pointer stores the address of a character type or address of the first character of a character array ( string ). Character pointers are very useful when you are working to manipulate the strings.

There is no string data type in C. An array of "char" type is considered as a string. Hence, a pointer of a char type array represents a string. This char pointer can then be passed as an argument to a function for processing the string.

Declaring a Character Pointer

A character pointer points to a character or a character array. Thus, to declare a character pointer, use the following syntax:

Initializing a Character Pointer

After declaring a character pointer, you need to initialize it with the address of a character variable. If there is a character array, you can simply initialize the character pointer by providing the name of the character array or the address of the first elements of it.

Character Pointer of Character

The following is the syntax to initialize a character pointer of a character type:

Character Pointer of Character Array

The following is the syntax to initialize a character pointer of a character array (string):

Character Pointer Example

In the following example, we have two variables character and character array. We are taking two pointer variables to store the addresses of the character and character array, and then printing the values of the variables using the character pointers.

Run the code and check its output −

The library functions in the header file "string.h" processes the string with char pointer parameters.

Understanding Character Pointer

A string is declared as an array as follows −

The string is a NULL terminated array of characters. The last element in the above array is a NULL character (\0).

Declare a pointer of char type and assign it the address of the character at the 0th position −

Remember that the name of the array itself is the address of 0th element.

A string may be declared using a pointer instead of an array variable (no square brackets).

This causes the string to be stored in the memory, and its address stored in ptr . We can traverse the string by incrementing the ptr .

Accessing Character Array

If you print a character array using the %s format specifier, you can do it by using the name of the character pointer. But if you want to access each character of the character array, you have to use an asterisk ( * ) before the character pointer name and then increment it.

Here is the full program code −

Alternatively, pass ptr to printf() with %s format to print the string.

On running this code, you will get the same output −

Character Pointer Functions

The "string.h" header files defines a number of library functions that perform string processing such as finding the length of a string, copying a string and comparing two strings. These functions use char pointer arguments.

The strlen() Function

The strlen() function returns the length, i.e. the number of characters in a string. The prototype of strlen() function is as follows −

The following code shows how you can print the length of a string −

When you run this code, it will produce the following output −

Effectively, the strlen() function computes the string length as per the user-defined function str_len() as shown below −

The strcpy() Function

The assignment operator ( = ) is not used to assign a string value to a string variable, i.e., a char pointer. Instead, we need to use the strcpy() function with the following prototype −

The following example shows how you can use the strcpy() function −

The strcpy() function returns the pointer to the destination string ptr1 .

Internally, the strcpy() function implements the following logic in the user-defined str_cpy() function −

When you runt his code, it will produce the following output −

The function copies each character from the source string to the destination till the NULL character "\0" is reached. After the loop, it adds a "\0" character at the end of the destination array.

The strcmp() Function

The usual comparison operators (<, >, <=, >=, ==, and !=) are not allowed to be used for comparing two strings. Instead, we need to use strcmp() function from the "string.h" header file. The prototype of this function is as follows −

The strcmp() function has three possible return values −

• When both strings are found to be identical , it returns "0".
• When the first not-matching character in str1 has a greater ASCII value than the corresponding character in str2, the function returns a positive integer . It implies that str1 appears after str2 in alphabetical order, as in a dictionary.
• When the first not-matching character in str1 has a lesser ASCII value than the corresponding character in str2, the function returns a negative integer . It implies that str1 appears before str2 in alphabetical order, as in a dictionary.

The following example demonstrates how you can use the strcmp() function in a C program −

Change s1 to BACK and run the code again. Now, you will get the following output −

You can obtain a similar result using the user-defined function str_cmp() , as shown in the following code −

The str_cmp() function compares the characters at the same index in a string till the characters in either string are exhausted or the characters are equal.

At the time of detecting unequal characters at the same index, the difference in their ASCII values is returned. It returns "0" when the loop is terminated.

Home » Learn C Programming from Scratch » C Character Type

C Character Type

Summary : in this tutorial, you will learn what C character type is and how to declare, use and print character variables in C.

C uses char type to store characters and letters. However, the char type is  integer type because underneath C stores integer numbers instead of characters.

To represent characters, the computer has to map each integer with a corresponding character using a numerical code. The most common numerical code is ASCII, which stands for American Standard Code for Information Interchange.

The following table illustrates the ASCII code:

For example, the integer number 65 represents a character A  in upper case.

In C, the char type has a 1-byte unit of memory so it is more than enough to hold the ASCII codes. Besides ASCII code, there are various numerical codes available such as extended ASCII codes. Unfortunately, many character sets have more than 127 even 255 values. Therefore, to fulfill those needs, Unicode was created to represent various available character sets. Unicode currently has over 40,000 characters.

Using C char  type

In order to declare a  variable with character type, you use the  char keyword followed by the variable name. The following example declares three char variables.

In this example, we initialize a character variable with a character literal. A character literal contains one character that is surrounded by a single quotation ( ' ).

The following example declares  key character variable and initializes it with a character literal ‘ A ‘:

Because the char type is the integer type, you can initialize or assign a char variable an integer. However, it is not recommended since the code may not be portable.

Displaying C character type

To print characters in C, you use the  printf()   function with %c  as a placeholder. If you use %d , you will get an integer instead of a character. The following example demonstrates how to print characters in C.

In this tutorial, you have learned about C character type and how to declare, use and print character variables in C.

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An operator is a symbol that operates on a value or a variable. For example: + is an operator to perform addition.

C has a wide range of operators to perform various operations.

C Arithmetic Operators

An arithmetic operator performs mathematical operations such as addition, subtraction, multiplication, division etc on numerical values (constants and variables).

Example 1: Arithmetic Operators

The operators + , - and * computes addition, subtraction, and multiplication respectively as you might have expected.

In normal calculation, 9/4 = 2.25 . However, the output is 2 in the program.

It is because both the variables a and b are integers. Hence, the output is also an integer. The compiler neglects the term after the decimal point and shows answer 2 instead of 2.25 .

The modulo operator % computes the remainder. When a=9 is divided by b=4 , the remainder is 1 . The % operator can only be used with integers.

Suppose a = 5.0 , b = 2.0 , c = 5 and d = 2 . Then in C programming,

C Increment and Decrement Operators

C programming has two operators increment ++ and decrement -- to change the value of an operand (constant or variable) by 1.

Increment ++ increases the value by 1 whereas decrement -- decreases the value by 1. These two operators are unary operators, meaning they only operate on a single operand.

Example 2: Increment and Decrement Operators

Here, the operators ++ and -- are used as prefixes. These two operators can also be used as postfixes like a++ and a-- . Visit this page to learn more about how increment and decrement operators work when used as postfix .

C Assignment Operators

An assignment operator is used for assigning a value to a variable. The most common assignment operator is =

Example 3: Assignment Operators

C relational operators.

A relational operator checks the relationship between two operands. If the relation is true, it returns 1; if the relation is false, it returns value 0.

Relational operators are used in decision making and loops .

Example 4: Relational Operators

C logical operators.

An expression containing logical operator returns either 0 or 1 depending upon whether expression results true or false. Logical operators are commonly used in decision making in C programming .

Example 5: Logical Operators

Explanation of logical operator program

• (a == b) && (c > 5) evaluates to 1 because both operands (a == b) and (c > b) is 1 (true).
• (a == b) && (c < b) evaluates to 0 because operand (c < b) is 0 (false).
• (a == b) || (c < b) evaluates to 1 because (a = b) is 1 (true).
• (a != b) || (c < b) evaluates to 0 because both operand (a != b) and (c < b) are 0 (false).
• !(a != b) evaluates to 1 because operand (a != b) is 0 (false). Hence, !(a != b) is 1 (true).
• !(a == b) evaluates to 0 because (a == b) is 1 (true). Hence, !(a == b) is 0 (false).

During computation, mathematical operations like: addition, subtraction, multiplication, division, etc are converted to bit-level which makes processing faster and saves power.

Bitwise operators are used in C programming to perform bit-level operations.

Visit bitwise operator in C to learn more.

Other Operators

Comma operator.

Comma operators are used to link related expressions together. For example:

The sizeof operator

The sizeof is a unary operator that returns the size of data (constants, variables, array, structure, etc).

Example 6: sizeof Operator

Other operators such as ternary operator ?: , reference operator & , dereference operator * and member selection operator  ->  will be discussed in later tutorials.

Table of Contents

• Arithmetic Operators
• Increment and Decrement Operators
• Assignment Operators
• Relational Operators
• Logical Operators
• sizeof Operator

Video: Arithmetic Operators in C

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C uses char type to store characters and letters. However, the char type is integer type because underneath C stores integer numbers instead of characters.In C, char values are stored in 1 byte in memory,and value range from -128 to 127 or 0 to 255. In order to represent characters, the computer has to map each integer with a corresponding character using a numerical code. The most common numerical code is ASCII, which stands for American Standard Code for Information Interchange.

How to declare characters?

To declare a character in C, the syntax:

Complete Example in C:

C library functions for characters

The Standard C library #include <ctype.h> has functions you can use for manipulating and testing character values:

How to convert character to lower case?

• int islower(ch)

Returns value different from zero (i.e., true) if indeed c is a lowercase alphabetic letter. Zero (i.e., false) otherwise.

How to convert character to upper case?

• int isupper(ch)

A value different from zero (i.e., true) if indeed c is an uppercase alphabetic letter. Zero (i.e., false) otherwise.

Check if character is an alphabet?

• isalpha(ch)

Returns value different from zero (i.e., true) if indeed c is an alphabetic letter. Zero (i.e., false) otherwise.

Check if character is a digit

• int isdigit(ch);

Returns value different from zero (i.e., true) if indeed c is a decimal digit. Zero (i.e., false) otherwise.

Check if character is a digit or alphabet

• int isalnum(ch);

Returns value different from zero (i.e., true) if indeed c is either a digit or a letter. Zero (i.e., false) otherwise.

Check if character is a punctuation

• int ispunct(ch)

Returns value different from zero (i.e., true) if indeed c is a punctuation character. Zero (i.e., false) otherwise.

Check if character is a space

• int isspace(ch)

Retuns value different from zero (i.e., true) if indeed c is a white-space character. Zero (i.e., false) otherwise.

• char tolower(ch) & char toupper(ch)

The value of the character is checked other if the vlaue is lower or upper case otherwise it is change and value is returned as an int value that can be implicitly casted to char.

Find size of character using Sizeof()?

To get the exact size of a type or a variable on a particular platform, you can use the sizeof operator. The expressions sizeof(type) yields the storage size of the object or type in bytes.

In the below example the size of char is 1 byte, but the type of a character constant like 'a' is actually an int, with size of 4.

• All the function in Ctype work under constant time

What are the different characters supported?

The characters supported by a computing system depends on the encoding supported by the system. Different encoding supports different character ranges.

Different encoding are:

ASCII encoding has most characters in English while UTF has characters from different languages.

Consider the following C++ code:

What will be the output of the above code?

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Character Arithmetic in C

As already known character range is between -128 to 127 or 0 to 255. This point has to be kept in mind while doing character arithmetic. 

What is Character Arithmetic ?

Character arithmetic is used to implement arithmetic operations like addition, subtraction, multiplication, and division on characters in C language.  In character arithmetic character converts into an integer value to perform the task. For this ASCII value is used. It is used to perform actions on the strings.

To understand better let’s take an example.

So %d specifier causes an integer value to be printed and %c specifier causes a character value to printed. But care has to taken that while using %c specifier the integer value should not exceed 127. 

Let’s take one more example.

Explanation 

• In this program, two character variables a and b are declared and assigned the values ‘A’ and ‘B’, respectively. The program then adds a and b using character arithmetic, which results ‘â’. The result is then printed using the printf() function.
• Note that in character arithmetic, the characters are treated as integers based on their ASCII code values. For example, the ASCII code for ‘A’ is 65 and for ‘B’ is 66, so adding ‘A’ and ‘B’ results in 65 + 66 = 131, which is the ASCII code for ‘â’.

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Assigning a value to a char array (String) in C [duplicate]

I tried to assign a String a value in C, but for me it doesn't work... This is, what I tried to do:

Sample Output would be: My Name is Dennis

However, I receive the a warning: warning: comparison of distinct pointer types lacks a cast k == "Dennis";

I tried to find a solution on this website, but could not find one, where it was the same error with assigning a value to a char array (a string) in C

Also tried initializing my char as

still didn't work...

• The code you posted 1) contains a syntax error and 2) doesn't produce the warning you claim it does. –  melpomene Commented Oct 21, 2017 at 16:28
• == is comparison, not assignment. = is assignment, but you cannot assign to an array. –  melpomene Commented Oct 21, 2017 at 16:28
• look at the library functions strcpy, strncpy –  CplusPuzzle Commented Oct 21, 2017 at 16:29
• Perhaps start off getting the code to compile! –  Ed Heal Commented Oct 21, 2017 at 16:36

You are indeed doing a comparison here: k == "Dennis" . So the compiler correctly warns you.

You probably meant k = "Dennis"; (fixed the missing semi-colon there). But that won't work either. Because in C arrays are not modifiable lvalues.

So you can either initialize the array:

or, use strcpy to copy:

If you actually have no need for an array , you can simply use a pointer that points to the string literal. The following is valid:

• The warning is about different pointer types, but the two types in question are both char * . –  melpomene Commented Oct 21, 2017 at 16:33
• thanks a lot! you are my hero! This works perfectly fine. –  Ayibogan Commented Oct 21, 2017 at 16:34
• @melpomene Perhaps OP posted the "wrong" code in the question. But the crux of the question remains the same. –  P.P Commented Oct 21, 2017 at 16:38

Not the answer you're looking for? Browse other questions tagged c or ask your own question .

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