Question

JAVA PROGRAM

1. Write a program to find the factorial value of any non-negative number entered through the keyboard.(method) (Factorial of n: n! = 1*2*3*…*n, 0! = 1.)

2. Write a program that prompts the user to input a positive integer. It should then output a message indicating whether the number is a prime number. (method)

Please post a screenshot of the codes. Thanks!

Answer 1

(1)

import java.util.Scanner;

//creating class factorial
public class Factorial {
   //Declare method for calculating factorial
   public int fact(int fact)
   {
       int f=1;
       for(int i=fact;i>0;i--)
       {
           f=f*i;
       }
       return f;
   }
   //main method
public static void main(String[] args) {
   //creating data variable
   int num;
   int fact = 1;
   //creating object of scanner class for taking input from user
   Scanner input=new Scanner(System.in);
   //creating object of our class
   Factorial fc=new Factorial();
   System.out.print("Enter a number: ");
   //taking input from user
   num=input.nextInt();
   //check number is greater then 0 or not
   if(num>=0)
   {
   fact=fc.fact(num);
   System.out.println("Factorial of "+num +" is :"+fact);
   }
   else {
       System.out.println("plz entered value greater then 0");
   }
      input.close();
}
}

screenshot -

Output-

(2)

import java.util.Scanner;

//creating class prime
public class Prime {
   //Declare method prime for check number is prime or not
public void isPrime(int num)
{
   int i,m=0,flag=0;
   m=num/2;
   if(num==0||num==1){
   System.out.println(num+" is not prime number");
   }else{
   for(i=2;i<=m;i++){
   if(num%i==0){
   System.out.println(num+" is not prime number");
   flag=1;
   break;
   }
   }
   if(flag==0) { System.out.println(num+" is prime number"); }
   }
  
}
public static void main(String[] args) {
   //creating object of scanner class for taking input from user
       Scanner input=new Scanner(System.in);
       //creating object of our class
       Prime prime=new Prime();
       System.out.print("enter positive Integer: ");
       //taking input from user
       int num=input.nextInt();
       if(num>=0)
       {
           //calling method isPrime
       prime.isPrime(num);  
       }
       else {
           System.out.println("Please enter a positive number");
       }
       input.close();
}
}

screenshot-

Output-