Strings in C

In C, strings are sequences of characters stored in character arrays and terminated by a null character \0.

In this lesson, you will learn:

• How to declare and initialize strings.
• How to manipulate strings using standard functions.
• The difference between character arrays and string literals.

Declaring a String

A string in C is declared as a character array.

Example:

char name[10];

This creates an array that can store a string of up to 9 characters plus the null terminator \0.

Initializing a String

Strings can be initialized in two ways:

• Using a character array:
char name[] = {'J', 'o', 'h', 'n', '\0'};
• Using a string literal:
char name[] = "John";

Printing a String

The printf function is used to print a string:

printf("%s", name);

Example:

char name[] = "Alice"; printf("Hello, %s!", name);

Example: Printing a String

This program demonstrates how to store and print a string.

#include <stdio.h>

int main() {
    char name[] = "Alice";
    printf("Hello, %s!\n", name);
    return 0;
}

String Input Using scanf()

To read a string input from the user, use scanf:

char name[20]; scanf("%s", name);

Warning: scanf does not read spaces in strings.

Example: Taking String Input

This program demonstrates how to take a string input using scanf.

#include <stdio.h>

int main() {
    char name[20];
    printf("Enter your name: ");
    scanf("%s", name);
    printf("Hello, %s!\n", name);
    return 0;
}

Common String Functions

C provides several string manipulation functions:

• strlen(str) - Returns string length.
• strcpy(dest, src) - Copies one string to another.
• strcat(dest, src) - Concatenates two strings.
• strcmp(str1, str2) - Compares two strings.

Summary

In this lesson, you learned:

• How to declare and initialize strings.
• How to print and take string input.
• How to use basic string functions.

Next, we will explore pointers and memory management in C!