# Java Program to Check Katadrome Number

In the previous article, we have discussed Java Program to Check Tcefrep Number

In this article we will see how to check a number is a Katadrome number or not in Java programming language.

## Java Program to Check Katadrome Number

Before going to the actual program, let’s first know what is a Katadrome Number.

Katadrome Number is a number whose digits are in decreasing digits.

Example:

4321
432
21
210
2
1
3
123
6710
13
890

Let’s see different ways to check katadrome number.

Approach:

1. Declare or take a number input.
2. Traverse all digits from right to left and check if any digit is smaller than previous. If smaller found then it is not katadrome number else it is a katadrome.

### Method-1: Java Program to Check Katadrome Number By Using Static Value

import java.util.*;

public class Main
{
public static void main(String[] args)
{

int number = 6541;
// Method Called
if (checkNumber(number))
else
System.out.print(number+" is not a Katadrome number");
}

// Method to check if a number is a Katadrome number or not
static boolean checkNumber(int number)
{

// To store previous digit
int previous = -1;

// Traversing all digits from right to left
// and checking if any digit is smaller than previous.
while (number > 0)
{
int digit = number % 10;
number /= 10;
if (digit < previous)
return false;
previous = digit;
}
return true;
}
}
Output:

6541 is a Katadrome number

### Method-2: Java Program to Check Katadrome Number By User Input Value

import java.util.*;

public class Main
{
public static void main(String[] args)
{
Scanner sc=new Scanner(System.in);
//a number declared
System.out.println("Enter a number:");
int number = sc.nextInt();
//Actualnumber assigned to atemp variable
int temp=number;
//flag valueinitialized as 1
int flag=1;

// To store previous digit
int previous = -1;

// Traversing all digits from right to left
// and checking if any digit is smaller than previous.
while (number > 0)
{
int digit = number % 10;
number /= 10;
if (digit < previous)
{
flag=0;
System.out.print(temp+" is not a Katadrome number");
break;
}
previous = digit;
}
if(flag==1)
}
}
Output:

Case-1

Enter a number:65

Case-2

Enter a number:659
659 is not a Katadrome number

### Method-3: Java Program to Check Katadrome Number By User Defined Method

import java.util.*;

public class Main
{
public static void main(String[] args)
{
Scanner sc=new Scanner(System.in);
int number = sc.nextInt();
// Method Called
if (checkNumber(number))
else
System.out.print(number+" is not a Katadrome number");
}

// Method to check if a number is a Katadrome number or not
static boolean checkNumber(int number)
{

// To store previous digit
int previous = -1;

// Traversing all digits from right to left
// and checking if any digit is smaller than previous.
while (number > 0)
{
int digit = number % 10;
number /= 10;
if (digit < previous)
return false;
previous = digit;
}
return true;
}
}
Output:

Case-1

4261 is not a Katadrome number