180119_1159_농구경기

//https://www.acmicpc.net/problem/1159

#include <iostream>

using namespace std;

int cntalphb[26];

int main()

{

int n;

cin >> n;

bool chk=0;

for(int i=0; i<n; i++)

{

char name[30];

cin >> name;

cntalphb[name[0]-'a']++;

}

for(int i=0; i<26; i++)

{

if(cntalphb[i]>=5)

{

chk=1;

cout << (char)(i+'a');

}

}

if(!chk) cout << "PREDAJA";

}