JAVA Tutorial-2

1. Write a program to display a random choice from a set of six choices for breakfast (you could use any set; for example, scrambled eggs, waffles, fruit, cereal, toast, or yogurt).
2. When testing whether an integer is a prime, it is sufficient to try to divide by integers up to the square root of the number being tested. Write a program to use this approach.
3. A lottery requires that you select six different numbers from the integers 1 to 49. Write a program to do this for you and generate five sets of entries.
4. Write a program to generate a random sequence of capital letters that does not include vowels.
5. Write an interactive program to print a string entrered in a pyramid form. For instance, the string “stream” has to be displayed as follows:

   S
   S t
   S t r
   S t r e
   S t r e a
   S t r e a m

6. Write an interactive program to print a diamond shape. For example, if user enters the number 3, the diamond will be as follows:

       *
      * *
     * * *
      * *
       *
      ...
   

1. Write a program to display a random choice from a set of six choices for breakfast (you could use any set; for example, scrambled eggs, waffles, fruit, cereal, toast, or yogurt).

 
import java.util.Random;
class choice
{
   public static void main(String args[])
   {
	Random randomGenerator = new Random();
	int r;
	r=randomGenerator.nextInt(6);
	System.out.println("random number="+r);
	System.out.println("1.scrambled eggs");
	System.out.println("2.waffles");
	System.out.println("3.fruit");
	System.out.println("4.cereal");
	System.out.println("5.toast");
	System.out.println("6.yogurt");
	switch(r)
	{
		case 1:
		  System.out.print("Your Choiced Value Is= scrambled eggs");
		break;
		case 2:
		  System.out.print("Your Choiced Value Is= waffles");
		break;
		case 3:
		  System.out.print("Your Choiced Value Is= furit");
		break;
		case 4:
		  System.out.print("Your Choiced Value Is= cereal");
		break;
		case 5:
		  System.out.print("Your Choiced Value Is= toast");
		break;
		case 6:
		  System.out.print("Your Choiced Value Is= Yogurt");
		break;
		default:
		  System.out.println("Invalid Choice");
		break;
	}
   }
}

Output

2. When testing whether an integer is a prime, it is sufficient to try to divide by integers up to the square root of the number being tested. Write a program to use this approach.

 
import java.util.Scanner;
class primeno
{
   public static void main(String ar[])
   {
	int n,sq,f=0,i;
	Scanner s=new Scanner(System.in);
	System.out.print("Enter a number to find wheather this number is prime number or not: ");
	n=s.nextInt();
	sq=(int)(Math.sqrt(n));
	for(i=sq;i<n;i++)
	{
		if((n%i)==0)
		{
			f=1;
			break;
		}
	}
	if(f==1)
	{
		System.out.println(+n+" is not prime number");
	}
	else
	{
		System.out.println(+n+" is prime number");
	}
   }
}

Output

3. A lottery requires that you select six different numbers from the integers 1 to 49. Write a program to do this for you and generate five sets of entries.

 
class lottery
{
   public static void main(String ar[])
   {
	int lucky,i,f=0;
	int a[]=new int[6];
	System.out.println("Ticket No");
	for(i=0;i<6;i++)
	{
		a[i]=(int)((6*Math.random())+1);
	}
	lucky=(int)((49*Math.random())+1);
	for(i=0;i<6;i++)
	{
		System.out.println(+a[i]);
	}	
	System.out.println("Lucky Number: "+lucky);
	for(i=0;i<6;i++)
	{
		if(a[i]==lucky)
		{
			f=1;
			break;
		}
	}
	if(f==1)
	{
		System.out.println(+lucky+" no ticket is winner");	
	}
	else
	{
		System.out.println("Sorry today no one is winner");
	}
   }
}
Output

4. Write a program to generate a random sequence of capital letters that does not include vowels.

 
import java.util.Random;
class vowels
{
   public static void main(String a[])
   {
	int i;
	Random r = new Random();
	char c[] = new char[5]; 
	for(i=0;i<5;i++)
	{
		c[i]=(char)(r.nextInt(26) + 'A');
	}
	for(i=0;i<5;i++)
	{ 
		switch(c[i])
		{
			case 'A':
			  System.out.println("Sorry this letter is vowel");
			break;
			case 'E':
			  System.out.println("Sorry this letter is vowel");
			break;
			case 'I':
			  System.out.println("Sorry this letter is vowel");
			break;
			case 'O':
			  System.out.println("Sorry this letter is vowel");
			break;
			case 'U':
			  System.out.println("Sorry this letter is vowel");
			break;
			default:
 			  System.out.println(c[i]);
   			break;
		}
	}
   }
}

Output

5. Write an interactive program to print a string entrered in a pyramid form. For instance, the string “stream” has to be displayed as follows:

S
S t
S t r
S t r e
S t r e a
S t r e a m

 
import java.io.*;
class pyramid
{
   public static void main(String a[])
   {
	char ch[]={'s','t','r','e','a','m'};
	String s=new String(ch);
	int i,j,k,n;
	n=s.length();
	for(i=n;i>0;i--)
	{
	        j=0;
		for(k=i;k<=n;k++)
		{
			System.out.print(ch[j]);
			System.out.print(" ");
			j++;
		}
		System.out.println("");
	}	
   }
}

Output

6. Write an interactive program to print a diamond shape. For example, if user enters the number 3, the diamond will be as follows:

    *
   * *
  * * *
   * *
    *
   ...

 
class diamond
{
   public static void main(String a[])
   {
	int i,j,k,n;
	n=Integer.parseInt(a[0]);
	for(i=n;i>0;i--)
	{
		for(j=0;j<i;j++)
		{
			System.out.print(" ");
		}
		j=0;
		for(k=i;k<=n;k++)
		{
			System.out.print("*");
			System.out.print(" ");
			j++;
		}
		System.out.println("");
	}
	for(i=n-1;i>0;i--)
	{
		for(j=i;j<=n;j++)
		{
			System.out.print(" ");
		}
		j=0;
		for(k=i;k>0;k--)
		{
			System.out.print("*");
			System.out.print(" ");
			j++;
		}
		System.out.println("");
	}
   }
}
Output