Find the First Non-Repeated Character

Given a string ( s ), your task is to find the first character that does not repeat anywhere in the string. If every character repeats, output an empty string.

For example, if ( s = ) "swiss", the first non-repeated character is "w". If ( s = ) "aabbcc", then there is no non-repeated character, so the output should be empty.

inputFormat

The input consists of a single line containing the string ( s ). The string may be empty and will only consist of ASCII characters.

outputFormat

Output the first non-repeated character in the string ( s ). If no such character exists, output an empty string.## sample

swiss

w