• 인자가 negative인지 판별

if 문을 통해서 해당 숫자가 0보다 작으면 N, 아니면 P

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_is_negative.c                                   :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: sungjpar <[email protected].>       +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2022/02/02 17:45:56 by sungjpar          #+#    #+#             */
/*   Updated: 2022/02/02 17:46:54 by sungjpar         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include <unistd.h>

void	ft_is_negative(int n);

void	ft_is_negative(int n)
{
	if (n < 0)
		write(1, "N", 1);
	else
		write(1, "P", 1);
}

• test case

void	ft_is_negative(int n);

int	main(void)
{
	int	i;
	int	j;
	int	k;

	i = -2147483648;
	j = 0;
	k = 2147483647;
	ft_is_negative(i);
	ft_is_negative(j);
	ft_is_negative(k);
}