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Palindrome Number
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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 are not the same. So, it is not a 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.
Code
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.
