#include <cstdio>

 #include <cstring>

 #include <algorithm>

 #include <string>

 #include <map>

 using namespace std;

 const int maxn =  + ;

 char buf[maxn];

 struct Edge{

     int to, next;

 }edge[maxn << ];

 int head[maxn], N;

 map<string, int> mapi;

 int n, k;

 int dp[maxn][];

 int o[maxn][];

 int get_str(char *dest){

     int cnt = ;

     char ch;

     do{

         ch = getchar();

     }while(ch != EOF && (ch == ' ' || ch == '\n'));

     if(ch == EOF) return ;

     dest[cnt++] = ch;

     while((ch = getchar()) != ' ' && ch != '\n' && ch != EOF) dest[cnt++] = ch;

     dest[cnt] = '\0';

     return cnt;

 }

 void addEdge(int u, int v){

     edge[N].next = head[u];

     edge[N].to = v;

     head[u] = N++;

 }

 void dfs(int u, int fa){

     dp[u][] = ;

     int tem1 = , tem2 = ;

     for(int i = head[u]; i + ; i = edge[i].next){

         int v = edge[i].to;

         if(v == fa) continue;

         dfs(v, u);

         dp[u][] += dp[v][];

         o[u][] |= o[v][];

         int d = dp[v][] > dp[v][] ?  : (dp[v][] == dp[v][] ? - : );

         if(d == -){

             dp[u][] += dp[v][];

             o[u][] = ;

         }else{

             dp[u][] += dp[v][d];

             o[u][] |= o[v][d];

         }

     }

 }

 int main(){

     //freopen("in.txt", "r", stdin);

     while(~scanf("%d", &n) && n){

         k = ;

         int base = ;

         get_str(buf);

         mapi.clear();

         mapi[string(buf)] = ++base;

         N = ;

         memset(head, -, sizeof head);

         for(int i = , x, y; i < n; i++){

             get_str(buf);

             if(mapi.find(string(buf)) == mapi.end()) mapi[string(buf)] = ++base, x = base;

             else x = mapi[string(buf)];

             get_str(buf);

             if(mapi.find(string(buf)) == mapi.end()) mapi[string(buf)] = ++base, y = base;

             else y = mapi[string(buf)];

             addEdge(x, y);

             addEdge(y, x);

         }

         memset(dp, , sizeof dp);

         memset(o, , sizeof o);

         dfs(, );

         int ans = -;

         bool ok = ;

         for(int i = ; i <= n; i++) for(int j = ; j <= ; j++){

             if(dp[i][j] > ans) ans = dp[i][j], ok = o[i][j];

             else if(dp[i][j] == ans) ok = ;

         }

         printf("%d %s\n", ans, ok ? "No" : "Yes");

     }

     return ;

 }