> For the complete documentation index, see [llms.txt](https://42-guide.gitbook.io/42-guide/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://42-guide.gitbook.io/42-guide/piscine-life/rushes/rush00/03.md).

# 03

### **Complete Solution and Explanation**

#### **1. Printing a Single Character (`ft_putchar`)**

```c
#include <unistd.h> // Includes write function for output

// Function to print a single character to standard output
void	ft_putchar(char c)
{
	write(1, &c, 1); // Writes character 'c' to standard output
}
```

✅ **Explanation:**

* Uses `write(1, &c, 1);` to print a character to the terminal.
* This function is used throughout the program to print characters.

***

#### **2. Printing the First Row (`first_line`)**

```c
// Function to print the first row of the rectangle
void	first_line(int width)
{
	int	i;

	i = 0;
	while (i < width) // Loop through the entire width
	{
		if (i == 0) // Print 'A' at the beginning
			ft_putchar('A');
		else if (i == width - 1) // Print 'C' at the end
			ft_putchar('C');
		else // Print 'B' for the middle characters
			ft_putchar('B');
		i++;
	}
	ft_putchar('\n'); // Move to the next line
}
```

✅ **Explanation:**

* **First character** is `'A'`.
* **Last character** is `'C'`.
* **Middle characters** are `'B'`, forming the horizontal border.
* Moves to a **new line** after printing the first row.

***

#### **3. Printing the Last Row (`last_line`)**

```c
// Function to print the last row of the rectangle
void	last_line(int width)
{
	int	i;

	i = 0;
	while (i < width) // Loop through the entire width
	{
		if (i == 0) // Print 'A' at the beginning
			ft_putchar('A');
		else if (i == width - 1) // Print 'C' at the end
			ft_putchar('C');
		else // Print 'B' for the middle characters
			ft_putchar('B');
		i++;
	}
	ft_putchar('\n'); // Move to the next line
}
```

✅ **Explanation:**

* **Same logic as `first_line()`**, because in **Rush 03**, the first and last rows are identical.
* Ensures the **first and last characters** are `'A'` and `'C'`.
* Moves to a **new line** after printing the last row.

***

#### **4. Printing the Middle Rows (`middle_rows`)**

```c
// Function to print the middle rows of the rectangle
void	middle_rows(int width, int height)
{
	int	i, j;

	for (j = 1; j < height - 1; j++) // Loop through each middle row
	{
		for (i = 0; i < width; i++) // Loop through characters in the row
		{
			if (i == 0 || i == width - 1) // Print 'B' for left and right borders
				ft_putchar('B');
			else // Print spaces in the middle
				ft_putchar(' ');
		}
		ft_putchar('\n'); // Move to the next line after finishing the row
	}
}
```

✅ **Explanation:**

* **Left and right borders** use `'B'`, ensuring vertical borders.
* **Middle section** consists of spaces `' '`, keeping the inside empty.
* Runs **only if height > 2**, ensuring enough space for a middle section.

***

#### **5. Printing the Full Rectangle (`rush`)**

```c
// Function to print the entire rectangle
void	rush(int width, int height)
{
	if (width <= 0 || height <= 0) // Handle invalid input (negative or zero values)
		return;

	first_line(width); // Print the first row

	if (height > 1) // Print middle rows only if height is greater than 1
		middle_rows(width, height);

	if (height > 1) // Print the last row only if height is greater than 1
		last_line(width);
}
```

✅ **Explanation:**

* **Handles edge cases** (if `width` or `height` is 0 or negative, it does nothing).
* Calls `first_line()`, `middle_rows()`, and `last_line()` **in sequence** to generate the full rectangle.
* The **middle rows and last row are printed only if `height > 1`**.

***

#### **6. Main Function (`main`)**

```c
// Main function to test the implementation
int	main(void)
{
	rush(5, 3); // Calls the function with width = 5, height = 3
	return (0);
}
```

✅ **Explanation:**

* Calls `rush(5,3)`, which prints a rectangle **5 characters wide and 3 characters high**.
* You can change values to test different rectangle sizes.

***

### **Summary of Functions and Responsibilities**

| Function Name   | Responsibility                                                            |
| --------------- | ------------------------------------------------------------------------- |
| `ft_putchar()`  | Prints a single character                                                 |
| `first_line()`  | Prints the first row with 'A' at start, 'C' at end, and 'B' in the middle |
| `last_line()`   | Prints the last row (identical to `first_line()`)                         |
| `middle_rows()` | Prints the middle rows with 'B' on edges and spaces inside                |
| `rush()`        | Calls all the row functions in order and checks for invalid input         |
| `main()`        | Starts the program and calls `rush()` with test dimensions                |

***

### **Example Outputs**

#### **Example 1: `rush(5, 3)`**

```
ABBBC
B   B
ABBBC
```

#### **Example 2: `rush(1, 1)`**

```
A
```

#### **Example 3: `rush(4, 4)`**

```
ABBC
B  B
B  B
ABBC
```


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