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# ft\_is\_negative

This exercise requires you to write a function `ft_is_negative` that checks the sign of an integer and displays either 'N' or 'P':

* 'N' if the number is negative.
* 'P' if the number is zero or positive.

#### Requirements:

* **Input:** An integer `n`.
* **Output:**
  * Print 'N' if the integer is negative.
  * Print 'P' if the integer is zero or positive.
* **Allowed Function:** Only `write` can be used for output.
* **Return Type:** The function should not return anything (`void`).

#### Steps:

1. **Check the sign of the number:**
   * If `n` is less than 0, print 'N' for negative.
   * Otherwise, print 'P' for positive or zero.
2. **Use the `write` function** to output 'N' or 'P'.

#### Code Implementation:

```c
#include <unistd.h>  // For the write function

void ft_is_negative(int n)
{
    if (n < 0)
        write(1, "N", 1);  // Write 'N' if the number is negative
    else
        write(1, "P", 1);  // Write 'P' if the number is zero or positive
}
```

#### Explanation:

* **Condition Check:**\
  The `if (n < 0)` condition checks if the integer `n` is negative. If it is, the function will print 'N'. If it's zero or positive, the function will print 'P'.
* **write Function:**
  * The `write` function is used to print the result. We pass:
    * `1` as the file descriptor for standard output.
    * A pointer to the string to print (`"N"` or `"P"`).
    * `1` as the number of bytes to write (since we're printing just one character).

#### Example of How to Test:

Here’s a simple `main.c` to test the `ft_is_negative` function:

```c
#include <unistd.h>

// Function prototype
void ft_is_negative(int n);

int main(void)
{
    ft_is_negative(-5);  // Output: N
    ft_is_negative(0);   // Output: P
    ft_is_negative(42);  // Output: P
    return 0;
}
```

#### Expected Output:

```css
N
P
P
```

* For `ft_is_negative(-5)`, it should print `'N'` since -5 is negative.
* For `ft_is_negative(0)` and `ft_is_negative(42)`, it should print `'P'` because both 0 and 42 are non-negative.

#### Key Points:

* **Handling Signs:** The function uses a simple `if` statement to check if the integer is negative or not.
* **System Call (`write`):** Just like previous exercises, we use the `write` system call to output the result directly to the terminal.

#### Conclusion:

This exercise tests your ability to work with conditionals and output simple characters based on the sign of an integer. It's very similar to the previous exercises, with the difference being that you're printing different characters based on the input integer's sign.

<mark style="color:red;">**Before submitting your project, comment out or remove your main function.**</mark>


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