libft/ft_atoi.c at main · edforte/libft · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_atoi.c                                          :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: edforte <edforte@student.42.fr>            +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2024/01/12 11:26:35 by edforte           #+#    #+#             */
/*   Updated: 2024/01/24 20:53:11 by edforte          ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "libft.h"

int	ft_atoi(const char *str)
{
	int	i;
	int	sign;
	int	res;

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