[Easy] Non Repeating Character

Given a string s consisting of lowercase Latin Letters, find the first non repeating character in s.

Input:

The first line contains T denoting the number of testcases. Then follows description of testcases.
Each case begins with a single integer N denoting the length of string. The next line contains the string s.

Output:

For each testcase, print the first non repeating character present in string.

Print -1 if there is no non repeating character.

Constraints:

1<=T<=50
1<=N<=100

Example:

Input:

3
5
hello
12
zxvczbtxyzvy
6
xxyyzz

Output: h
c
-1

def non_repeating_chr(str):
    list1 = list(str)
    for i in range(len(list1)):
        if list1.count(list1[i]) == 1:
            return list1[i]
    return -1

t = int(input())
for i in range(t):
    n = int(input())
    str = input()
    print(non_repeating_chr(str))