diff --git a/headers/philo_proto.h b/headers/philo_proto.h
index 20f068d..3e5bf23 100644
--- a/headers/philo_proto.h
+++ b/headers/philo_proto.h
@@ -6,7 +6,7 @@
 /*   By: hulamy <marvin@42.fr>                      +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2022/01/26 15:27:13 by hulamy            #+#    #+#             */
-/*   Updated: 2022/01/26 15:29:49 by hulamy           ###   ########.fr       */
+/*   Updated: 2022/01/26 17:50:11 by hulamy           ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -29,6 +29,10 @@ int		diff_time(t_time *old, struct timeval *new);
 int		print_message(t_philo *philo, char *clr, char *msg);
 
 // utils.c
+int		ft_isdigit_2d_arr(char **str);
+size_t	ft_strlen(char *str);
+int		ft_strncmp(char *s1, char *s2, size_t n);
+int		ft_int_overflow(char *str);
 int		ft_atoi(const char *str);
 
 #endif
diff --git a/srcs/init.c b/srcs/init.c
index f1d3040..3b03b91 100644
--- a/srcs/init.c
+++ b/srcs/init.c
@@ -6,7 +6,7 @@
 /*   By: hulamy <hulamy@student.42.fr>              +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2022/01/26 15:30:34 by hulamy            #+#    #+#             */
-/*   Updated: 2022/01/26 16:29:38 by hulamy           ###   ########.fr       */
+/*   Updated: 2022/01/26 17:55:34 by hulamy           ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -57,22 +57,29 @@ static t_philo	*init_chain_philo(t_params *params, t_global *global)
 static t_params	*init_params(int ac, char **av)
 {
 	t_params	*params;
+	int			i;
 
-	if (ac == 5 || ac == 6)
-	{
-		params = malloc(sizeof(t_params));
-		if (!params)
-			return (NULL);
-		params->n_phi = ft_atoi(av[1]);
-		params->t_die = ft_atoi(av[2]);
-		params->t_eat = ft_atoi(av[3]);
-		params->t_slp = ft_atoi(av[4]);
-		params->n_eat = -1;
-		if (ac == 6)
-			params->n_eat = ft_atoi(av[5]);
-	}
-	else
+	if (ac < 5 || ac > 6)
 		return (NULL);
+	if (!ft_isdigit_2d_arr(av + 1))
+		return (NULL);
+	i = 0;
+	while (av[i])
+	{
+		if (ft_int_overflow(av[i]))
+			return (NULL);
+		i++;
+	}
+	params = malloc(sizeof(t_params));
+	if (!params)
+		return (NULL);
+	params->n_phi = ft_atoi(av[1]);
+	params->t_die = ft_atoi(av[2]);
+	params->t_eat = ft_atoi(av[3]);
+	params->t_slp = ft_atoi(av[4]);
+	params->n_eat = -1;
+	if (ac == 6)
+		params->n_eat = ft_atoi(av[5]);
 	return (params);
 }
 
diff --git a/srcs/utils.c b/srcs/utils.c
index 48ef485..53546e5 100644
--- a/srcs/utils.c
+++ b/srcs/utils.c
@@ -1,17 +1,79 @@
 /* ************************************************************************** */
 /*                                                                            */
 /*                                                        :::      ::::::::   */
-/*   generic.c                                          :+:      :+:    :+:   */
+/*   utils.c                                            :+:      :+:    :+:   */
 /*                                                    +:+ +:+         +:+     */
 /*   By: hulamy <marvin@42.fr>                      +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2022/01/26 15:30:19 by hulamy            #+#    #+#             */
-/*   Updated: 2022/01/26 15:31:15 by hulamy           ###   ########.fr       */
+/*   Updated: 2022/01/26 17:50:31 by hulamy           ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
 #include "philo.h"
 
+int	ft_isdigit_2d_arr(char **str)
+{
+	int	i;
+	int	j;
+
+	i = 0;
+	while (str[i])
+	{
+		j = 0;
+		while (str[i][j])
+		{
+			if (str[i][j] < '0' || str[i][j] > '9')
+				return (0);
+			j++;
+		}
+		i++;
+	}
+	return (1);
+}
+
+size_t	ft_strlen(char *str)
+{
+	size_t i;
+
+	i = 0;
+	while (str[i])
+		i++;
+	return (i);
+}
+
+int	ft_strncmp(char *s1, char *s2, size_t n)
+{
+	size_t	i;
+	int		res;
+
+	i = 0;
+	res = 0;
+	while (s1[i] && s1[i] == s2[i] && i < n - 1)
+		i++;
+	if (n != 0)
+		res = (unsigned char)s1[i] - (unsigned char)s2[i];
+	return (res);
+}
+
+int ft_int_overflow(char *str)
+{
+	size_t  len;
+	char	*int_xtrem;
+
+	int_xtrem = "2147483647";
+	if (str[0] == '-')
+		int_xtrem = "2147483648";
+	if (str[0] == '+' || str[0] == '-')
+		str++;
+	len = ft_strlen(str);
+    if (len < 10)
+        return (0);
+    else if (len > 10 || ft_strncmp(str, int_xtrem, len) > 0)
+        return (1);
+    return (0);
+}
+
 int	ft_atoi(const char *str)
 {
 	int	i;