Sieve of Eratosthenes Java

Given a number n, program to print all primes smaller than or equal to n. It is also given that n is a small number. 


class SieveOfEratosthenes
{
    void sieveOfEratosthenes(int n)
    {
        // Create a boolean array "prime[0..n]" and initialize
        // all entries it as true. A value in prime[i] will
        // finally be false if i is Not a prime, else true.
        boolean prime[] = new boolean[n+1];
        for(int i=0;i<n;i++)
            prime[i] = true;
          
        for(int p = 2; p*p <=n; p++)
        {
            // If prime[p] is not changed, then it is a prime
            if(prime[p] == true)
            {
                // Update all multiples of p
                for(int i = p*p; i <= n; i += p)
                    prime[i] = false;
            }
        }
          
        // Print all prime numbers
        for(int i = 2; i <= n; i++)
        {
            if(prime[i] == true)
                System.out.print(i + " ");
        }
    }
      
    // Driver Program to test above function
    public static void main(String args[])
    {
        int n = 30;
        System.out.print("Following are the prime numbers ");
        System.out.println("smaller than or equal to " + n);
        SieveOfEratosthenes g = new SieveOfEratosthenes();
        g.sieveOfEratosthenes(n);
    }
}

OUTPUT

Following are the prime numbers smaller than or equal to 30
2 3 5 7 11 13 17 19 23 29

CREDITS: https://www.geeksforgeeks.org/sieve-of-eratosthenes/

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