libft/ft_itoa.c at main · LilianMS/libft · GitHub

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/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_itoa.c                                          :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: lilmende <lilmende@student.42sp.org.br>    +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2023/11/04 10:41:52 by lilmende          #+#    #+#             */
/*   Updated: 2023/11/04 11:26:52 by lilmende         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "libft.h"

static int	count_digits(int n)
{
	int	count;

	count = 0;
	if (n <= 0)
		count = 1;
	while (n)
	{
		count++;
		n /= 10;
	}
	return (count);
}

char	*ft_itoa(int n)
{
	char	*str;
	int		count;

	count = count_digits(n);
	str = (char *)malloc(sizeof(char) * (count + 1));
	if (!str)
		return (NULL);
	str[count] = '\0';
	if (n == 0)
		str[0] = '0';
	if (n < 0)
		str[0] = '-';
	while (n)
	{
		if (n > 0)
			str[--count] = '0' + (n % 10);
		else
			str[--count] = '0' + (n % 10 * -1);
		n /= 10;
	}
	return (str);
}