Basketball Game

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Time limit1sMemory limit128 MB

Summary

Given N surnames, count first letters and print all letters (in order) that start at least five surnames, or PREDAJA if none does.

Level: Easy2 of 10
Topics: Hash map, Implementation, String
Solved: No attempts yet

Problem

A national basketball coach must choose a starting lineup for the next match. To make the lineup easy to remember, the coach wants to choose five players whose surnames start with the same lowercase English letter.

For every first letter that appears in at least five players' surnames, that letter can be used to form such a lineup. Find all possible first letters.

Input

The first line contains the number of players N (1 <= N <= 150).

Each of the next N lines contains one player's surname. Each surname consists only of lowercase English letters and has length at most 30.

Output

If no first letter appears in at least five surnames, print PREDAJA.

Otherwise, print all qualifying first letters in lexicographic order with no spaces between them.

Examples2

Example 1

Input

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

Expected output

bk

Example 2

Input

6
michael
jordan
lebron
james
kobe
bryant

Expected output

PREDAJA