#include <iostream>
#include <cmath>
#include <iostream>
#define el "\n"
using namespace std;
bool isprime(int n)
{
if (n <= 1)
{
return 0;
}
for(int i=2 ; i <= sqrt(n); i++) // [sqrt(n)] is faster in calculations than [n/2]
{
if(n%i == 0)
{
return 0;
}
}
return 1;
};
int main()
{
long long num;
cin >> num; // ~~~ Enter a number
(isprime(num))? cout << "The number (" << num <<") is a prime" << el : cout << "The number (" << num <<") isn't a prime" << el;
return 0;
}
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>>"))))
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;
}
}