ft_atoi.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_atoi.c                                          :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: antandre <antandre@student.42barcel>       +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2024/05/01 16:03:43 by antandre          #+#    #+#             */
/*   Updated: 2024/05/01 16:27:15 by antandre         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

/*
 * The atoi() function converts the initial portion of the string pointed
 * to by nptr to int. Return the converted value or 0 on error.
 */

int	ft_atoi(const char *nptr)
{
	int	sign;
	int	result;
	int	i;

	result = 0;
	sign = 1;
	i = 0;
	while (nptr[i] == 32 || (nptr[i] >= 9 && nptr[i] <= 13))
		i++;
	if (nptr[i] == '-')
		sign *= -1;
	if (nptr[i] == '+' || nptr[i] == '-')
		i++;
	while (nptr[i] >= '0' && nptr[i] <= '9')
	{
		result = result * 10 + nptr[i] - '0';
		i++;
	}
	return (result * sign);
}