#include <iostream>
#include <vector>
#include <string>
#include <queue>
using namespace std;

int num;

vector<int> adj[26];

vector<int> ltfz[26];

int conn[26][26] = {0};

bool state[26] = {false};

//int state3[26] = {0};

bool kexing[26][3] = {false};

int yx[26][3] = {0};

bool dfs(int, int);

void init(){
	for(int i = 0; i < 26; i++){
		for(int j = 0; j < 3; j++){
			kexing[i][j] = true;
		}
	}
	for(int i = 0; i < 26; i++){
		for(int j = 0; j < 3; j++) yx[i][j] = -1;
	}
	for(int i = 0; i < 26; i++) {
		adj[i].clear();
	}
	for(int i = 0; i < 26; i++){
		ltfz[26].clear();
	}
	for(int i = 0; i < 26; i++){
		state[i] = false;
	}
	for(int i = 0; i < 26; i++){
		for(int j = 0; j < 26; j++){
			conn[i][j] = 0;
		}
	}
}

int main() {
	while(1){
		init();
		cin >> num;
		//cout << num << endl;
		if(num == 0) return num;
		int cnt = 0;
		for(int i = 0; i < num; i++){
			string s;
			cin >> s;
			int len = s.length();
			for(int j = 2; j < len; j++){
				conn[i][s[j]-'A'] = 1;
				adj[i].push_back(s[j]-'A');
				cnt++;
			}
		}
		if(cnt == 0){
			cout << "1 channel needed." << endl;
			continue;
		}
		int ltfzgs = 0;
		bool ers[26];
		for(int i = 0; i < num; i++){
			if(state[i]) continue;
			state[i] = true;
			ers[i] = true;
			queue<int> bfs;
			bfs.push(i);
			ltfz[ltfzgs].push_back(i);
			while(!bfs.empty()){
				int thi = bfs.front();
				bfs.pop();
				int sz = adj[thi].size();
				for(int j = 0; j < sz; j++){
					int idx = adj[thi][j];
					if(state[idx]) continue;
					bfs.push(idx);
					if(ers[thi]) ers[idx] = false;
					else ers[idx] = true;
					ltfz[ltfzgs].push_back(idx);
					state[idx] = true;
				}
			}
			ltfzgs++;
		}
		bool kyers = true;
		for(int i = 0; i < num; i++){
			int sz = adj[i].size();
			for(int j = 0; j < sz; j++){
				if((ers[i] + ers[adj[i][j]])%2 == 0){
					kyers = false;
					goto wanle;
				}
			}
		}
		wanle:
		if(kyers){
			cout << "2 channels needed." << endl;
			continue;
		}
		bool kysrs = true;
		for(int i = 0; i < ltfzgs; i++){
			int sz = ltfz[i].size();
			if(sz <= 3) continue;
			for(int j = 1; j < sz; j++){
				for(int k = j; k > 0; k--){
					if(adj[ltfz[i][k]].size() <= adj[ltfz[i][k-1]].size()) break;
					int temp = ltfz[i][k];
					ltfz[i][k] = ltfz[i][k-1];
					ltfz[i][k-1] = temp;
				}
			}
			for(int j = 0; j < adj[ltfz[i][0]].size(); j++){
				kexing[adj[ltfz[i][0]][j]][0] = false;
				yx[adj[ltfz[i][0]][j]][0] = ltfz[i][0];
			}
			if(!dfs(i, sz-1)){
				kysrs = false;
				break;
			}
		}
		if(kysrs) cout << "3 channels needed." << endl;
		else cout << "4 channels needed." << endl;
	}
	return 0;
}


bool dfs(int i, int gs){
	if(gs == 0) return true;
	int sz = ltfz[i].size();
	int kldd = ltfz[i][sz - gs];
	if(kexing[kldd][0]){
		for(int j = 0; j < adj[kldd].size(); j++){
			if(kexing[adj[kldd][j]][0]){
				kexing[adj[kldd][j]][0] = false;
				yx[adj[kldd][j]][0] = kldd;
			}
		}
		if(dfs(i, gs-1)) return true;
		for(int j = 0; j < adj[kldd].size(); j++){
			if(!kexing[adj[kldd][j]][0] && yx[adj[kldd][j]][0] == kldd){
				kexing[adj[kldd][j]][0] = true;
				yx[adj[kldd][j]][0] = -1;
			}
		}
	}
	if(kexing[kldd][1]){
		for(int j = 0; j < adj[kldd].size(); j++){
					if(kexing[adj[kldd][j]][1]){
						kexing[adj[kldd][j]][1] = false;
						yx[adj[kldd][j]][1] = kldd;
					}
				}
				if(dfs(i, gs-1)) return true;
				for(int j = 0; j < adj[kldd].size(); j++){
					if(!kexing[adj[kldd][j]][1] && yx[adj[kldd][j]][1] == kldd){
						kexing[adj[kldd][j]][1] = true;
						yx[adj[kldd][j]][1] = -1;
					}
				}
	}
	if(kexing[kldd][2]){
		for(int j = 0; j < adj[kldd].size(); j++){
					if(kexing[adj[kldd][j]][2]){
						kexing[adj[kldd][j]][2] = false;
						yx[adj[kldd][j]][2] = kldd;
					}
				}
				if(dfs(i, gs-1)) return true;
				for(int j = 0; j < adj[kldd].size(); j++){
					if(!kexing[adj[kldd][j]][2] && yx[adj[kldd][j]][2] == kldd){
						kexing[adj[kldd][j]][2] = true;
						yx[adj[kldd][j]][2] = -1;
					}
				}
	}
	return false;
}