Taking advantage of the ascii table tricks

ft_toupper, ft_tolower, ft_atoi, ft_itoa

4 files changed, 24 insertions, 28 deletions

diff --git a/ft_atoi.c b/ft_atoi.c
index 17488fa..bfba860 100644
--- a/ft_atoi.c
+++ b/ft_atoi.c
@@ -6,48 +6,38 @@
 /*   By: cacharle <marvin@42.fr>                    +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2019/10/07 09:46:16 by cacharle          #+#    #+#             */
-/*   Updated: 2019/10/19 10:50:39 by cacharle         ###   ########.fr       */
+/*   Updated: 2019/11/20 01:43:18 by cacharle         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
+#include "libft.h"
+
 #define MIN_INT -2147483648
 #define MAX_INT 2147483647
 
-static int	precheck(const char **str)
-{
-	int is_negative;
-
-	while (**str == ' ' || **str == '\t' || **str == '\n'
-			|| **str == '\v' || **str == '\f' || **str == '\r')
-		(*str)++;
-	is_negative = 0;
-	if (**str == '-' || **str == '+')
-	{
-		if (**str == '-')
-			is_negative = 1;
-		(*str)++;
-	}
-	return (is_negative);
-}
-
 int			ft_atoi(const char *str)
 {
 	unsigned int	nb;
 	int				i;
 	int				is_negative;
 
-	is_negative = precheck(&str);
+	while (*str == ' ' || *str == '\t' || *str == '\n'
+			|| *str == '\v' || *str == '\f' || *str == '\r')
+		str++;
+	is_negative = 0;
+	if (*str == '-' || *str == '+')
+		if (*str++ == '-')
+			is_negative = 1;
 	i = 0;
 	nb = 0;
-	while (str[i] >= '0' && str[i] <= '9')
+	while (ft_isdigit(str[i]))
 	{
 		if (!is_negative && nb > (unsigned int)MAX_INT)
 			return (-1);
 		else if (nb > (unsigned int)MIN_INT)
 			return (0);
 		nb *= 10;
-		nb += str[i] - '0';
-		i++;
+		nb += str[i++] & 0x0F;
 	}
 	return ((int)(is_negative ? -nb : nb));
 }
diff --git a/ft_itoa.c b/ft_itoa.c
index 426937e..03d794b 100644
--- a/ft_itoa.c
+++ b/ft_itoa.c
@@ -6,7 +6,7 @@
 /*   By: cacharle <marvin@42.fr>                    +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2019/10/07 10:19:56 by cacharle          #+#    #+#             */
-/*   Updated: 2019/10/07 10:21:23 by cacharle         ###   ########.fr       */
+/*   Updated: 2019/11/20 01:15:40 by cacharle         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -56,7 +56,7 @@ char		*ft_itoa(int n)
 	len--;
 	while (len >= (is_negative ? 1 : 0))
 	{
-		str[len] = u_nbr % 10 + '0';
+		str[len] = (u_nbr % 10) | 0x30;
 		u_nbr /= 10;
 		len--;
 	}
diff --git a/ft_tolower.c b/ft_tolower.c
index 6a252aa..919469f 100644
--- a/ft_tolower.c
+++ b/ft_tolower.c
@@ -6,13 +6,19 @@
 /*   By: cacharle <marvin@42.fr>                    +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2019/10/07 10:14:26 by cacharle          #+#    #+#             */
-/*   Updated: 2019/10/20 13:04:16 by cacharle         ###   ########.fr       */
+/*   Updated: 2019/11/20 01:04:02 by cacharle         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
+/*
+** E: 0100 0101
+** e: 0110 0101
+**      ^
+*/
+
 int	ft_tolower(int c)
 {
 	if (c >= 'A' && c <= 'Z')
-		return (c + 'a' - 'A');
+		return (c | 0b00100000);
 	return (c);
 }
diff --git a/ft_toupper.c b/ft_toupper.c
index 0257786..8579b91 100644
--- a/ft_toupper.c
+++ b/ft_toupper.c
@@ -6,7 +6,7 @@
 /*   By: cacharle <marvin@42.fr>                    +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2019/10/07 10:14:10 by cacharle          #+#    #+#             */
-/*   Updated: 2019/10/07 10:14:20 by cacharle         ###   ########.fr       */
+/*   Updated: 2019/11/20 01:04:51 by cacharle         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -15,6 +15,6 @@
 int	ft_toupper(int c)
 {
 	if (c >= 'a' && c <= 'z')
-		return (c - 'a' + 'A');
+		return (c ^ 0b00100000);
 	return (c);
 }