Description

You are given $n$ strings. Each string has its corresponding first letter.

Output the number of first letters whose corresponding number of strings is at least $5$.

Input Format

The first line contains a positive integer $n$.

The next $n$ lines each contain a string consisting only of lowercase letters, with length not exceeding $30$ characters.

Output Format

If there is no first letter that meets the requirement, output PREDAJA.

Otherwise, output all such first letters in lexicographical order, with no spaces.

18
babic
keksic
boric
bukic
sarmic
balic
kruzic
hrenovkic
beslic
boksic
krafnic
pecivic
klavirkovic
kukumaric
sunkic
kolacic
kovacic
prijestolonasljednikovic 

bk 

6
michael
jordan
lebron
james
kobe
bryant 

PREDAJA

Hint

Explanation for Sample 1

The first letters that meet the requirement are k and b.

Constraints

For $100\%$ of the testdata, $1\le n\le 150$.

Notes

$\mathtt{Subtask\ 0}$ is the sample.

$\mathtt{Subtask\ 1\sim 2}$ has no special restrictions.

This problem is translated from COCI2013-2014 CONTEST #1 T1 TRENER.

Translated by ChatGPT 5