prime numbers

[ladislav]

Hello,I neead help with simple program in java.First test prime numbers with use array and second with use two method,thank.
Simi.

[r035198x]

Hello,I neead help with simple program in java.First test prime numbers with use array and second with use two method,thank.
Simi.

Surely you should have some ideas of your own on how to do this. Why don't you post the ideas then others can add their own.

[ladislav]

I need modify this code.

for(int pp=2;pp<100;pp++) //pp=possible prime
{
for(int pd=2;pd<pp;pd++) //pd=possible divisor
{
if(pp%pd==0)
break;
}
if(pp==pd)
System.out.println(pp);
}

[r035198x]

I need modify this code.

for(int pp=2;pp<100;pp++) //pp=possible prime
{
for(int pd=2;pd<pp;pd++) //pd=possible divisor
{
if(pp%pd==0)
break;
}
if(pp==pd)
System.out.println(pp);
}

public class Primes {
    public static void main(String[] args) {
        int pp, pd = 0;
        for(pp=2;pp<100;pp++) //pp=possible prime
        {
        for(pd=2;pd<pp;pd++) //pd=possible divisor
        {
        if(pp%pd==0)
        break;
        }
        if(pp==pd)
        System.out.println(pp);
        }
    }
}

This will print all primes from 2 - 97. What exactly do you want to do?

[ladislav]

I don´t know how pp replace by array obout 100 numbers?

[r035198x]

I don´t know how pp replace by array obout 100 numbers?

Do you mean that you want to store the primes in an array of size 100? You would do it this way:

public class Primes {
        public static void main(String[] args) {
    int[] primes = new int[100];
    int i = 0;
    int pp, pd = 0;
    for(pp=2;pp<100;pp++) //pp=possible prime
    {
         for(pd=2;pd<pp;pd++) //pd=possible divisor
             {
        if(pp%pd==0)
        break;
        }
        if(pp==pd)
        primes[i++] = pp;
        }
        for(int p: primes) {
            System.out.println(p);
        }
 
    }
}

I'm sorry, but you are not being very clear

[ladislav]

I am much obliged with the help of.