diff --git a/utils/ft_isnum.c b/utils/ft_isnum.c
index f78e9ad..298b91e 100644
--- a/utils/ft_isnum.c
+++ b/utils/ft_isnum.c
@@ -6,21 +6,28 @@
 /*   By: cchauvet <cchauvet@student.42angoulem      +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2023/03/08 14:43:33 by cchauvet          #+#    #+#             */
-/*   Updated: 2023/04/11 14:47:30 by cchauvet         ###   ########.fr       */
+/*   Updated: 2023/04/19 13:49:58 by cchauvet         ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
 #include "../philo.h"
+#include <stddef.h>
+#include <limits.h>
 
 bool	ft_isnum(char str[])
 {
 	size_t	i;
+	size_t	num;
 
+	num = 0;
 	i = 0;
 	while (str[i] != '\0')
 	{
 		if (str[i] > '9' || str[i] < '0')
 			return (0);
+		num = num * 10 + str[i] - 48;
+		if (num > INT_MAX)
+			return (0);
 		i++;
 	}
 	return (1);