/*
0214sh7's validation
*/

#include<bits/stdc++.h>
#include "testlib.h"
using namespace std;

const long long MIN_N = 2, MAX_N = 1'000'000;
const long long MIN_M = 1, MAX_M = 500'000;
const long long MIN_T = 2, MAX_T = 1'000'000;

int main(){
    registerValidation();
    long long N = inf.readLong(MIN_N, MAX_N);
    inf.readSpace();
    long long M = inf.readLong(MIN_M, MAX_M);
    inf.readEoln();

    long long Tsum = 0;
    for(int i=0;i<M;i++){
        
        int t = inf.readLong(2, N);
        inf.readSpace();
        Tsum += t;
        vector<long long> S(t);
        for(int j=0;j<t;j++){
            S[j] = inf.readLong(1, N);

            if(j!=t-1){
                inf.readSpace();
            }else{
                inf.readEoln();
            }
        }

        sort(S.begin(),S.end());
        for(int j=0;j<t-1;j++){
            assert(S[j]!=S[j+1]);
        }
    }

    assert(MIN_T <= Tsum && Tsum <= MAX_T);

    inf.readEof();
    return 0;
}