- Time limit: 1.00 s
- Memory limit: 512 MB
Uolevi recently created a new programming language. The programming language has only the following three functions for manipulating strings:
new (c)
- takes a character c and creates a string that consists of a single character c.
expand (S, c)
- takes a string S and a character c and creates the string ScS.
reverse (S)
- reverses the string S.
Your task is to find out if a given string could have been created using Uolevi's programming language.
Input
The only line of input contains one string of length n. The string consists of lowercase english letters.
Output
Output 10-4
if the string could have been created by Uolevi's programming language and QAQ
otherwise.
Constraints
- 1 \le n \le 2000
Examples
Input:
abacaba
Output:
10-4
Input:
uolevi
Output:
QAQ