Challenge Information

Title : Do not Repeat Character
Difficulty : Easy
Solutions : 21
Maximum Score : 50
Completed by You: No
Description :

There is a string of lower-case Latin letters given. You have to find the first non-repeating character in the given string.

Write a function solve that have the following parameter(s):
1.) a = a string

Example
Input:
a= call
Output:
c

Explanation
The first non-repeating character is "c".

Example
Input:
a= happy
Output:
h

Explanation
The first non-repeating character is "h".

Constraints

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