def is_prime(n):
if(n<0):
print("n is not a nature number!")
return False
for i in range(1,ceil(n/2)+1):
if (i != n and i != 1 and n%i == 0):
return False
return True
print(is_prime(int(input("number>>"))))number = int(input("please enter a number: "))
lis = [2, 3, 5, 7] # list of first 4 prime numbers
lis2 = [i for i in lis if number % i == 0] # if the number is prime, this list (lis 2) will be empty or that it's one of the first elements in lis which are prime numbers
if len(lis2) == 0 or number in lis:
print("Number is prime!")
else:
print("Number is NOT prime!")
using System;
public class Program
{
static void Main(string[] args)
{
var results = GenerateSieve(1000);
var i=0;
foreach (var item in results)
{
if(item) Console.Write(i + " ");
i++;
}
}
static bool[] GenerateSieve(int num)
{
// Creating an array indicating whether numbers are prime.
bool[] isPrime = new bool[num + 1];
for (int i = 2; i <= num; i++) isPrime[i] = true;
// Removing out multiples.
for (int i = 2; i <= num; i++)
{
// Check if i is prime.
if (isPrime[i])
{
// Eliminate multiples of i.
for (int j = i * 2; j <= num; j += i)
isPrime[j] = false;
}
}
return isPrime;
}
}import java.util.Scanner;
public class Prime {
public static void main (String[] args) {
Scanner userInput = new Scanner(System.in);
int n = userInput.nextInt();
if (!(n % 2 == 0) || n == 2) {
System.out.println("not prime");
} else {
System.out.println("prime");
}
}
}