diff --git a/Makefile b/Makefile
index 8d0a8a4..9bc6286 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,7 @@
 #    By: tmaze <marvin@42.fr>                       +#+  +:+       +#+         #
 #                                                 +#+#+#+#+#+   +#+            #
 #    Created: 2018/04/04 10:51:59 by tmaze             #+#    #+#              #
-#    Updated: 2018/04/05 13:16:24 by tmaze            ###   ########.fr        #
+#    Updated: 2018/04/05 14:13:58 by tmaze            ###   ########.fr        #
 #                                                                              #
 #******************************************************************************#
 
@@ -29,6 +29,7 @@ SRCS =	\
 		ft_strnstr.c \
 		ft_strcmp.c  \
 		ft_strncmp.c \
+		ft_atoi.c	 \
 		ft_isalpha.c \
 		ft_isdigit.c \
 		ft_isalnum.c \
diff --git a/ft_atoi.c b/ft_atoi.c
new file mode 100644
index 0000000..d1985cc
--- /dev/null
+++ b/ft_atoi.c
@@ -0,0 +1,40 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   ft_atoi.c                                          :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: tmaze <marvin@42.fr>                       +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2018/04/05 13:50:22 by tmaze             #+#    #+#             */
+/*   Updated: 2018/04/05 14:24:13 by tmaze            ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "libft.h"
+
+int		ft_atoi(const char *str)
+{
+	int	nbnum;
+	int	mult;
+	int ret;
+
+	nbnum = 0;
+	while (str[nbnum] == ' ' || str[nbnum] == '\t' || str[nbnum] == '\n'\
+			|| str[nbnum] == '\v' || str[nbnum] == '\f' || str[nbnum] == '\r')
+		nbnum++;
+	if (str[nbnum] == '+' || str[nbnum] == '-')
+		nbnum++;
+	while (str[nbnum] != '\0' && str[nbnum] >= '0' && str[nbnum] <= '9')
+		nbnum++;
+	nbnum--;
+	ret = 0;
+	mult = 1;
+	while (nbnum >= 0 && (str[nbnum] >= '0' && str[nbnum] <= '9'))
+	{
+		ret += (str[nbnum--] - '0') * mult;
+		mult *= 10;
+	}
+	if (nbnum >= 0 && str[nbnum] == '-')
+		ret *= -1;
+	return (ret);
+}
diff --git a/libft.h b/libft.h
index 907f129..028da87 100644
--- a/libft.h
+++ b/libft.h
@@ -6,7 +6,7 @@
 /*   By: tmaze <marvin@42.fr>                       +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2018/04/04 10:40:01 by tmaze             #+#    #+#             */
-/*   Updated: 2018/04/05 13:11:35 by tmaze            ###   ########.fr       */
+/*   Updated: 2018/04/05 13:51:17 by tmaze            ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -40,7 +40,7 @@ char	*ft_strstr(const char *haystack, const char *needle);
 char	*ft_strnstr(const char *haystack, const char *needle, size_t len);
 int		ft_strcmp(const char *s1, const char *s2);
 int		ft_strncmp(const char *s1, const char *s2, size_t n);
-int		ft_atoi(const char *nptr);
+int		ft_atoi(const char *str);
 int		ft_isalpha(int c);
 int		ft_isdigit(int c);
 int		ft_isalnum(int c);