#include<bits/stdc++.h> using namespace std; string a,word[105]; bool cmp(string aa,string aaa){ return aa<aaa; } int main(){ string n; getline(cin,n); getline(cin,a); string s=""; int len=0; for(int i=0;i<a.size();i++){ if(a[i]>='a'&&a[i]<='z'||a[i]>='A'&&a[i]<='Z'&&a[i]!=' '){ s+=a[i]; if(i==a.size()-1) word[len++] = s; } else{ if(s=="") continue; word[len++]=s; s=""; } } sort(word,word+len,cmp); for(int i=0;i<len;i++){ if(i!=0&&word[i]==word[i-1]) continue; else cout<<word[i]<<endl; } return 0; }