Java Coding Question

*
***
****
*****

class A
{
    public static void main(String args[])
    {
        int i,j;
        for(i=1;i<=5;i++) // rows
        {
            for(j=1;j<=i;j++) // cols
            {
                System.out.print("*");
            }
            System.out.print("\n");
        }
    }
}

    * 
  * * * 
* * * * *

class A
{
    public static void main(String args[])
    {
        int i,j,k;
        for(i=1;i<=3;i++) // Rows
        {
            for(j=i;j<3;j++) // spaces
            {
                System.out.print("  ");
            }
            for(k=1;k<=2*i-1;k++) // Odd Numbers (1, 3, 5)
            {
                System.out.print("* ");
            }
            System.out.print("\n");
        }
    }
}

Basic Array Programs - Java

Fibonnaci Series

import java.util.Scanner;

public class FibonacciSeries
{
    public static void main(String[] args)
    {
        int term, a=0, b=1, temp;

        System.out.print("Enter Terms: ");
        Scanner r = new Scanner(System.in);
        term = r.nextInt();

        for(int i=1; i<=term; i++)
        {
            System.out.print(a +" ");
            temp=a+b;
            a=b;
            b=temp;
        }
    }
}

Reverse String in Java

import java.util.Scanner;
public class ReverseString
{
    public static void main(String[] args)
    {
        // String str= "Vivek";

        System.out.println("\nEnter String: ");
        Scanner st = new Scanner(System.in);
        String str = st.nextLine();
        String rev= "";

        int len = str.length(); //5

        for(int i=len-1; i>=0; i--) // 4 3 2 1 0
        {
            rev = rev + str.charAt(i); // V i v e k
        }
        System.out.println("\nReversed number is: "+ rev);
    }
}

Palindrome Number

import java.util.Scanner;
public class PalindromeNumber
{
    public static void main(String[] args)
    {
        Scanner sc= new Scanner(System.in);
        System.out.print("\nEnter Number: ");
        int num = sc.nextInt();

        int original = num; // checking whether both no. equal or not

        int rev=0;
        while(num!=0)
        {
            rev = rev*10 + num%10;
            num = num/10;
        }
        if(original==rev)
        {
            System.out.println("Plaindrome Number");
        }
        else
        {
            System.out.println("Not Plaindrome Number");
        }
    }
}