uva 247

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//
//        GGGGGGGGGGGGG        CCCCCCCCCCCCC               AAA
//     GGG::::::::::::G     CCC::::::::::::C              A:::A
//   GG:::::::::::::::G   CC:::::::::::::::C             A:::::A
//  G:::::GGGGGGGG::::G  C:::::CCCCCCCC::::C            A:::::::A
// G:::::G       GGGGGG C:::::C       CCCCCC           A:::::::::A
//G:::::G              C:::::C                        A:::::A:::::A
//G:::::G              C:::::C                       A:::::A A:::::A
//G:::::G    GGGGGGGGGGC:::::C                      A:::::A   A:::::A
//G:::::G    G::::::::GC:::::C                     A:::::A     A:::::A
//G:::::G    GGGGG::::GC:::::C                    A:::::AAAAAAAAA:::::A
//G:::::G        G::::GC:::::C                   A:::::::::::::::::::::A
// G:::::G       G::::G C:::::C       CCCCCC    A:::::AAAAAAAAAAAAA:::::A
//  G:::::GGGGGGGG::::G  C:::::CCCCCCCC::::C   A:::::A             A:::::A
//   GG:::::::::::::::G   CC:::::::::::::::C  A:::::A               A:::::A
//     GGG::::::GGG:::G     CCC::::::::::::C A:::::A                 A:::::A
//        GGGGGG   GGGG        CCCCCCCCCCCCCAAAAAAA                   AAAAAAA
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <climits>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <cctype>
#include <utility>
#include <string>
#include <ctime>
using namespace std;
#ifdef DEBUG
#define debug(...) printf("DEBUG: "),printf(__VA_ARGS__)
#define gettime() end_time=clock();printf("now running time is %.7f\n",(float)(end_time - start_time)/CLOCKS_PER_SEC);
#else
#define debug(...)
#define gettime()
#endif
typedef unsigned int uint;
typedef long long int Int;
#define Set(a,s) memset(a,s,sizeof(a))
#define Write(w) freopen(w,"w",stdout)
#define Read(r) freopen(r,"r",stdin)
#define Pln() printf("\n")
#define I_de(x,n)for(int i=0;i<n;i++)printf("%d ",x[i]);Pln()
#define De(x)printf(#x"%d\n",x)
#define For(i,x)for(int i=0;i<x;i++)
#define CON(x,y) x##y
#define Pmz(dp,nx,ny)for(int hty=0;hty<ny;hty++){for(int htx=0;htx<nx;htx++){\
    printf("%d ",dp[htx][hty]);}Pln();}
#define M 55
#define PII pair<int,int>
#define PB push_back
#define oo INT_MAX
#define Set_oo 0x3f
#define FOR(it,c) for(vector<PII>::iterator it=(c).begin();it!=(c).end();it++)
#define eps 1e-6
clock_t start_time=clock(), end_time;
bool xdy(double x,double y){return x>y+eps;}
bool xddy(double x,double y){return x>y-eps;}
bool xcy(double x,double y){return x<y-eps;}
bool xcdy(double x,double y){return x<y+eps;}
int min3(int x,int y,int z){
    int tmp=min(x,y);
    return min(tmp,z);
}
int max3(int x,int y,int z){
    int tmp=max(x,y);
    return max(tmp,z);
}
int n,m;
map<string,int> sid;
map<int,string> rsid;
int mz[M][M];
int st[M];
bool inst[M];
int top;
int low[M],dis[M];
int connum[M];
int con[M][M];
int allcon;
int t;
void dfs(int x){
    low[x]=dis[x]=++t;
    inst[x]=1;
    st[top++]=x;
    for(int i=0;i<n;i++){
        if(mz[x][i]){
            if(!dis[i])dfs(i);
            if(inst[i]){
                low[x]=min(low[x],low[i]);
            }
        }
    }
    if(dis[x]==low[x]){
        int j;
        do{
            j=st[--top];
            inst[j]=0;
            con[allcon][connum[allcon]++]=j;
        }while(x!=j);
        allcon++;
    }
}
void solve(){
    t=top=allcon=0;
    Set(dis,0);
    Set(connum,0);
    for(int i=0;i<n;i++){
        if(!dis[i])dfs(i);
    }
    for(int i=0;i<allcon;i++){
        printf("%s",rsid[con[i][0]].c_str());
        for(int j=1;j<connum[i];j++){
            printf(", %s",rsid[con[i][j]].c_str());
        }Pln();
    }
}
int main() {
    ios_base::sync_with_stdio(0);
    int ff=0;
    while(~scanf("%d%d",&n,&m)&&n+m){
        sid.clear();
        rsid.clear();
        Set(mz,0);
        char str[1000],str2[1000];
        int cnt=0;
        for(int i=0;i<m;i++){
            scanf("%s%s",str,str2);
            if(!(sid.count(str))){
                sid[str]=cnt++;
                rsid[cnt-1]=str;
            }
            if(!(sid.count(str2))){
                sid[str2]=cnt++;
                rsid[cnt-1]=str2;
            }
            int x=sid[str],y=sid[str2];
            mz[x][y]=1;
        }
        if(ff)Pln();
        printf("Calling circles for data set %d:\n",++ff);
        solve();
    }
















}