String in C

In C programming, a string is a sequence of characters stored in an array. In C, strings are represented as null-terminated arrays of characters, where the null character ('\0') marks the end of the string. C does not have a built-in string data type like some other programming languages, so strings are typically manipulated using character arrays.

Here are some key points about strings in C:

1. String Declaration

• Strings in C are declared as character arrays with an additional element to store the null character ('\0').
• The array size should be large enough to accommodate the string characters plus the null character.

Syntax:

char string_name[size];

Example:

char name[20];  // Declaration of a character array to store a string of up to 19 characters

2. String Initialization:

• Strings can be initialized during declaration or assigned later using the strcpy() function.
• To initialize a string during declaration, you enclose the characters within double quotes.

Syntax:

char string_name[] = "string_value";

Example:

char greeting[] = "Hello, world!";  // Initialization of a string during declaration

3. String Input:

• You can read a string from the user using the scanf() function or the gets() function (although gets() is considered unsafe).

Example using scanf()

char name[20];
printf("Enter your name: ");
scanf("%s", name);  // Reads a string from the user and stores it in the name array

4. String Output:

• You can print a string using the printf() function or the puts() function.

Example using printf():

char name[] = "John";
printf("Hello, %s!\n", name);  // Output: Hello, John!

Example using puts():

char name[] = "John";
puts(name);  // Output: John

String Manipulation:

• Strings can be manipulated using various library functions from the header.
• Common string functions include strlen(), strcpy(), strcat(), strcmp(), and others.

#include <string.h>

char source[] = "Hello";
char destination[20];

strcpy(destination, source);  // Copies the content of source into destination
strcat(destination, " world!");  // Concatenates " world!" to destination

int length = strlen(destination);  // Gets the length of the string in destination

printf("%s\n", destination);  // Output: Hello world!
printf("Length: %d\n", length);  // Output: Length: 12

Strings in C are a fundamental and widely used data type. They allow you to work with sequences of characters, perform string manipulation operations, and interact with input/output functions for textual data. However, it's important to handle strings carefully to avoid buffer overflow issues and ensure proper null-termination.