Non repeating character.py

class Solution:
    def nonrepeatingCharacter(self, s):
        dic = {}
        for i in s:
            if i in dic:
                dic[i] += 1
            else:
                dic[i] = 1

        for i in s:
            if dic[i] == 1:
                return i

        return "$"


# {
# Driver Code Starts
# Initial Template for Python 3

import atexit
import io
import sys

_INPUT_LINES = sys.stdin.read().splitlines()
input = iter(_INPUT_LINES).__next__
_OUTPUT_BUFFER = io.StringIO()
sys.stdout = _OUTPUT_BUFFER


@atexit.register
def write():
    sys.__stdout__.write(_OUTPUT_BUFFER.getvalue())


if __name__ == "__main__":
    t = int(input())
    for i in range(t):
        s = str(input())
        obj = Solution()
        ans = obj.nonrepeatingCharacter(s)
        if ans != "$":
            print(ans)
        else:
            print(-1)

# } Driver Code Ends