Question

int is_prime(int n)
{
if (n <= 1) return 0;
if (n % 2 == 0 && n > 2) return 0;
for (int i = 3; i < n / 2; i += 2)
if (n % i == 0)
return 0;
return 1;
}

What do the three lines in this function mean?

Answer 1

Program:

import java.io.*;
import java.util.Scanner;
public class TestPrime { // Here taking class name as TestPrime
public int is_prime(int n) { // Definition of the method is_prime()
/*if (n <= 1)
return 0; //The above condition is true then returning 0 to the main()
if (n % 2 == 0 && n > 2)
return 0; //The above condition is true then returning 0 to the main() */
for (int i = 3; i < n / 2; i += 2)
if (n % i == 0) //Here checking the condition if remainder is zero
return 0; //The above condition is true then returning 0 to the main()
return 1;
}
public static void main(String args[]) // Start of main()
{
int m=0; // Here initializing the value of integer varaible called yr
TestPrime ob = new TestPrime(); // Here creating the object for class TestPrime
Scanner in = new Scanner(System.in);
System.out.println("Enter Value of n: "); // Here taking Input from the User
m = in.nextInt(); // Here scanning the input
System.out.println(ob.is_prime(m)); // Here calling the leapyear() method
}// End of main()
} // End of class TestPrime

Output: