#include<bits/stdc++.h>
using namespace std;
int ans,k,ok;
string s,g[105];
int main(){
	cin>>s;
	for (int i=0;i<s.size();++i){
		if (s[i]==','){
			ok=0;
			ans=0;
			++k;
			continue;
		}
		++ans;
		if (ok) continue;
		if ((s[i]>='a' && s[i]<='z') || (s[i]>='A' && s[i]<='Z') || (s[i]>='0' && s[i]<='9') || s[i]=='!' || s[i]=='@' || s[i]=='#' || s[i]=='$'){
			g[k]+=s[i];
			continue;
		}
		g[k]="";
		ok=1;
	}
	int i=0;
	while (!g[i].empty()){
		if (g[i].size()+1>=6 && g[i].size()+1<=12) cout<<g[i]<<'\n';
		++i;
	}
	return 0;
}