What's the second non-repeating character? Based on this question from Code Review

Given a non-empty string of printable ASCII characters, output the second non-repeating character. For example, for input DEFD, output F.

Input


A single string, in any suitable format.


Output


The second character that doesn't repeat, when reading left-to-right, again in a suitable format.
The output character is case-insensitive.
If no such character exists (e.g., all characters repeat), output an empty string.


Rules


The algorithm should ignore case. That is, D and d count as the same character.
Either a full program or a function are acceptable.
The input string will be guaranteed non-empty (i.e., at least one character in length).
The input string is ASCII. Any valid character could repeat, not just alphanumeric (this includes spaces).
Standard loopholes are forbidden.
This is code-golf so all usual golfing rules apply, and the shortest code (in bytes) wins.


Examples

Input is on first line, output is on second line.

DEFD
F

FEED
D

This is an example input sentence.
x

...,,,..,,!@
@

ABCDefgHijklMNOPqrsTuVWxyz
B

AAAAAABBBBB


Thisxthis


This this.
.
MATL, 11 bytes
tk&amp;=s1=)FT)

This exits with an error (allowed by default) if there is no second non-repeated character.
Try it online!
Explanation
t      % Implicitly take input string. Duplicate
k      % Convert to lowercase
&amp;=     % 2D array of equality comparisons
s      % Sum of each column
1=     % True for entries that equal 1
)      % Apply logical index to the input string to keep non-repeated characters
TF)    % Apply logical index to take 2nd element if it exists. Implicitly display