9766: ABC260 —— A - A Unique Letter
[Creator : ]
Description
You are given a string $S$ of length $3$.
Print a character that occurs only once in $S$.
If there is no such character, print `-1` instead.
Print a character that occurs only once in $S$.
If there is no such character, print `-1` instead.
Input
Input is given from Standard Input in the following format:
```
$S$
```
```
$S$
```
Output
Print the answer. If multiple solutions exist, you may print any of them.
Constraints
- $S$ is a string of length $3$ consisting of lowercase English letters.
Sample 1 Input
pop
Sample 1 Output
o
o occurs only once in pop.
Sample 2 Input
abc
Sample 2 Output
a
a, b, and c occur once each in abc, so you may print any of them.
Sample 3 Input
xxx
Sample 3 Output
-1
No character occurs only once in xxx.