c04/c05 testing + c06

1 files changed, 31 insertions, 0 deletions

diff --git a/c05/ex06/ft_is_prime.c b/c05/ex06/ft_is_prime.c
new file mode 100644
index 0000000..05628a2
--- /dev/null
+++ b/c05/ex06/ft_is_prime.c
@@ -0,0 +1,31 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   ft_is_prime.c                                      :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: cacharle <charles.cabergs@gmail.com>       +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2019/07/06 20:17:59 by cacharle          #+#    #+#             */
+/*   Updated: 2019/07/07 08:27:21 by cacharle         ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+int ft_is_prime(int nb)
+{
+	int	i;
+
+	if (nb <= 1)
+		return (0);
+	if (nb <= 3)
+		return (1);
+	if (nb % 2 == 0 || nb % 3 == 0)
+		return (0);
+	i = 5;
+	while (i * i <= nb)
+	{
+		if (nb % i == 0 || nb % (i + 2) == 0)
+			return (0);
+		i += 6;
+	}
+	return (1);
+}