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# C03

In this module, you’ll deepen your understanding of string manipulation by working with comparison, concatenation, and search functions in C. This section focuses on reproducing fundamental string-processing functions, helping you better understand how they work at a lower level.

***

#### **What You'll Learn:**

**String Comparison:**

* Implement functions that compare strings character by character to determine their lexicographical order.

**String Concatenation:**

* Join strings together while handling buffer limitations safely.

**String Search:**

* Locate substrings within larger strings using efficient methods.

**Reproducing Standard Library Functions:**

* Implement versions of standard C functions like `strcmp`, `strncpy`, `strcat`, `strstr`, and `strlcat`.

***

#### **Projects in This Section:**

1. **ft\_strcmp**
   * Reproduce `strcmp` to compare two strings and return their difference.
   * Prototype: `int ft_strcmp(char *s1, char *s2);`
2. **ft\_strncmp**
   * Reproduce `strncmp` to compare up to `n` characters of two strings.
   * Prototype: `int ft_strncmp(char *s1, char *s2, unsigned int n);`
3. **ft\_strcat**
   * Reproduce `strcat` to concatenate two strings.
   * Prototype: `char *ft_strcat(char *dest, char *src);`
4. **ft\_strncat**
   * Reproduce `strncat` to concatenate up to `n` characters from `src` to `dest`.
   * Prototype: `char *ft_strncat(char *dest, char *src, unsigned int nb);`
5. **ft\_strstr**
   * Reproduce `strstr` to find the first occurrence of a substring within a string.
   * Prototype: `char *ft_strstr(char *str, char *to_find);`
6. **ft\_strlcat**
   * Reproduce `strlcat` to concatenate strings while ensuring a buffer size limit.
   * Prototype: `unsigned int ft_strlcat(char *dest, char *src, unsigned int size);`

***

These exercises will strengthen your ability to work with strings and pointers in C. You'll gain a deeper understanding of how standard string functions operate internally, preparing you for more advanced C programming concepts.


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