Question

java question, my questions are in the following codes with comments, just answer next or under it thanks!

theres only few, so no worry.

import java.security.SecureRandom;

public class clsTestRand {

   public static void main(String[] args) {
       // TODO Auto-generated method stub
       //int num1, num2, num3, num4, num5, num6;
       int num1 = 0;
       int num2 = 0;
       int num3 = 0;
       int num4 = 0;
       int num5 = 0;
      
      
       SecureRandom rn = new SecureRandom(); /
      
       for (int i= 1; i<=10; i++) // so random numbers between 1 to 10 right?
       {
           int roll =1 +rn.nextInt(6);// add 1 because it does not count 6, count from 0 (this one isn't question, we are just assuming that this is a dice)
      
           switch (roll)
           {
           case 1:
               ++num1; // why do we use ++ ? and what it does?
               break;
           case 2:
           ++num2;
           break;
           case 3:
               ++num3;
               break;
           case 4:
               ++num4;
               break;
           case 5:
               ++num5;
               break;
          
           }//end switch
          
       }//end for loop
      
       System.out.println("1: "+num1); // +num1 using println was equal to printf %d%n, so I guess it's just different way right? so it's like " : " + variable + variable if we want more than 1 variable if we need it inside println?
       System.out.printf("2: %d%n", num2);
       System.out.printf("3: %d%n", num3);
       System.out.printf("4: %d%n", num4);
       System.out.printf("5: %d%n", num5);
      
   }

}

Answer 1

import java.security.SecureRandom;

public class clsTestRand {

   public static void main(String[] args) {
       // TODO Auto-generated method stub
       //int num1, num2, num3, num4, num5, num6;
       int num1 = 0;
       int num2 = 0;
       int num3 = 0;
       int num4 = 0;
       int num5 = 0;
      
      
       SecureRandom rn = new SecureRandom(); /
      
       for (int i= 1; i<=10; i++) // so random numbers between 1 to 10 right?

//NO its not random number between 1 and 10, It repeats following statements within the block 10 times, so to generate 10 //random numbers and do operations on them
       {
           int roll =1 +rn.nextInt(6);// add 1 because it does not count 6, count from 0 (this one isn't question, we are just assuming that this is a dice)
      
           switch (roll)
           {
           case 1:
               ++num1; // why do we use ++ ? and what it does?

//++num1 is pre increment operator,it increases the value of num1 by 1 and then assigns it.
               break;
           case 2:
           ++num2;
           break;
           case 3:
               ++num3;
               break;
           case 4:
               ++num4;
               break;
           case 5:
               ++num5;
               break;
          
           }//end switch
          
       }//end for loop
      
       System.out.println("1: "+num1); // +num1 using println was equal to printf %d%n, so I guess it's just different way right? so it's like " : " + variable + variable if we want more than 1 variable if we need it inside println?

//println("1: "+num1) is like printf("1: %d",num1)....to print more than one variable in println, use println(" "+num1+" "+num2+" //"+num3)
       System.out.printf("2: %d%n", num2);
       System.out.printf("3: %d%n", num3);
       System.out.printf("4: %d%n", num4);
       System.out.printf("5: %d%n", num5);
      
   }

}