//

 //by coolxxx

 //#include<bits/stdc++.h>

 #include<iostream>

 #include<algorithm>

 #include<string>

 #include<iomanip>

 #include<map>

 #include<memory.h>

 #include<time.h>

 #include<stdio.h>

 #include<stdlib.h>

 #include<string.h>

 //#include<stdbool.h>

 #include<math.h>

 #define min(a,b) ((a)<(b)?(a):(b))

 #define max(a,b) ((a)>(b)?(a):(b))

 #define abs(a) ((a)>0?(a):(-(a)))

 #define lowbit(a) (a&(-a))

 #define sqr(a) ((a)*(a))

 #define swap(a,b) ((a)^=(b),(b)^=(a),(a)^=(b))

 #define mem(a,b) memset(a,b,sizeof(a))

 #define eps (1e-8)

 #define J 10

 #define mod 1000000007

 #define MAX 0x7f7f7f7f

 #define PI 3.14159265358979323

 #define N 104

 using namespace std;

 typedef long long LL;

 int cas,cass;

 int n,m,lll,ans;

 double anss;

 string s1[N];

 struct xxx

 {

     int next,to;

 }a[N];

 int last[N];

 bool mark[N];

 bool cmp(string aa,string bb)

 {

     if(aa.length()!=bb.length())return aa.length()<bb.length();

     int i;

     for(i=;i<aa.length();i++)

         if(aa[i]!=bb[i])return aa[i]<bb[i];

 }

 void add(int x,int y)

 {

     a[++lll].next=last[x];

     a[lll].to=y;

     last[x]=lll;

 }

 string dfs(int u)

 {

     string s[N];

     int i,j;

     for(i=last[u],j=;i;i=a[i].next,j++)

         s[j]=dfs(a[i].to);

     sort(s+,s++j,cmp);

     string t="(";

     for(i=;i<=j;i++)t+=s[i];

     t=t+")";

 //    cout<<u<<" "<<t<<endl;

     return t;

 }

 int main()

 {

     #ifndef ONLINE_JUDGE

 //    freopen("1.txt","r",stdin);

 //    freopen("2.txt","w",stdout);

     #endif

     int i,j,k;

     int x,y;

 //    for(scanf("%d",&cas);cas;cas--)

 //    for(scanf("%d",&cas),cass=1;cass<=cas;cass++)

 //    while(~scanf("%s",s+1))

     while(~scanf("%d",&m))

     {

         scanf("%d",&n);

         for(i=;i<=m;i++)

         {

             lll=;

             mem(last,);mem(mark,);

             for(j=;j<n;j++)

             {

                 scanf("%d%d",&x,&y);

                 add(x,y);mark[y]=;

             }

             for(j=;j<=n;j++)if(!mark[j])break;

             s1[i]=dfs(j);

         }

         mem(mark,);

         for(i=;i<=m;i++)

         {

             if(mark[i])continue;

             printf("%d",i);

             mark[i]=;

             for(j=i+;j<=m;j++)

                 if(s1[i]==s1[j])

                 {

                     printf("=%d",j);

                     mark[j]=;

                 }

             puts("");

         }

     }

     return ;

 }

 /*

 //

 //

 */