Reverse String if Even Length

Given a non-empty string s, write a program that outputs its reverse if the length of s is even; otherwise, output the original string. Formally, if |s| \mod 2 = 0, output \(s^R\) (i.e. the reverse of s), otherwise output s unchanged.

For example:

• If s = "abcd" (length 4), then output "dcba".
• If s = "abc" (length 3), then output "abc".

The input is provided from standard input and the result must be printed to standard output.

inputFormat

The input consists of a single line containing a string s. The string may be empty. Read the input from standard input (stdin).

outputFormat

Output a single line to standard output (stdout): if the length of s is even, output the reverse of s; otherwise, output s as it is.

abcd

dcba