## Palindrome Number

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### Description

A number is said to be a palindrome number if the number is equal to its reverse. For example, if a number is 121 then the reverse of the number is also 121. Therefore, this number is a palindrome. But if the number is 123, then the reverse of this number is 321. Here, the number and the reverse is not same. So, it is not palindrome.

### Algorithm

INPUT: A number

OUTPUT: Whether the number is a palindrome or not.

PROCESS:

Step 1: [Taking the input]

Read n [the number to be checked]

Step 2: [Checking the number]

Set m<-n

Set rev<-0

[Reversing the number]

While n>0 repeat

Set rev<-rev×10 + (n mod 10)

Set n<-n/10

[End of ‘for’ loop]

If m=rev then

Print "The number is palindrome"

Else

Print "The number is not palindrome"

[End of ‘if’]

[End of checking for ‘palindrome’]

Step 3: Stop.

## TIME COMPLEXITY:

while(n>0)-----------------------------------O(m)

{

rev=rev*10+(n%10);

n=n/10;

}

The time complexity of checking a number is O(m) where m is the number of digits of the given number.

## SPACE COMPLEXITY:

The space complexity of this program is O(1) as it requires a constant number of space to execute for any given input.