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

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/* ************************************************************************** */
/*                                                                            */
/*                                                        ::::::::            */
/*   ft_itoa.c                                          :+:    :+:            */
/*                                                     +:+                    */
/*   By: mgraaf <mgraaf@student.codam.nl>             +#+                     */
/*                                                   +#+                      */
/*   Created: 2021/12/16 14:21:55 by mgraaf        #+#    #+#                 */
/*   Updated: 2021/12/16 14:21:59 by mgraaf        ########   odam.nl         */
/*                                                                            */
/* ************************************************************************** */

#include "libft.h"

int	determine_length(long long n, int neg_or_pos)
{
	int	i;

	i = 0;
	if (n == 0)
		i++;
	while (n > 0)
	{
		n = n / 10;
		i++;
	}
	if (neg_or_pos)
		i++;
	return (i);
}

char	*fill_arr(long long n, char *arr, int i, int neg_or_pos)
{
	arr[i] = '\0';
	i--;
	if (n == 0)
	{
		arr[i] = '0';
		i--;
	}
	while (n > 0)
	{
		arr[i] = (n % 10) + '0';
		i--;
		n = n / 10;
	}
	if (neg_or_pos)
	{
		arr[i] = '-';
		i++;
	}
	return (arr);
}

char	*ft_itoa(int n)
{
	int			i;
	int			neg_or_pos;
	char		*arr;
	long long	j;

	neg_or_pos = 0;
	if (n < 0)
	{
		neg_or_pos = 1;
		j = (long long)n * -1;
	}
	else
		j = (long long)n;
	i = determine_length(j, neg_or_pos);
	arr = malloc(i * sizeof(char) + 1);
	if (!arr)
		return (0);
	arr = fill_arr(j, arr, i, neg_or_pos);
	return (arr);
}