//Author:Daneii
#include <bits/stdc++.h>

using namespace std;
//快读
template <typename T>inline void read(T& t)
{
    int f=0;
    t=0;
    char ch=getchar();
    while(!isdigit(ch))
    {
        if(ch=='-')
            f=1;
        ch=getchar();
    }
    while(isdigit(ch))
    {
        t=t*10+ch-48;
        ch=getchar();
    } 
    t=f?-t:t;
}
template <typename T,typename... Args> inline void read(T& t, Args&... args){read(t);read(args...);}

const int N=2e5+10;

int n,m;
vector<int> g[N];
int deg[N];

bool topsort()
{
    queue<int> q;
    for(int i=1;i<=n;i++)
        if(!deg[i])
            q.push(i);

    int cnt=0;
    while(q.size())
    {
        auto tmp=q.front();
        q.pop();
        cnt++;
        for(auto x:g[tmp])
        {
            if(--deg[x]==0)
            {
                q.push(x);
            }
        }
    }

    return cnt==n;
}

int main()
{
    read(n,m);

    for(int i=1;i<=m;i++)
    {
        int k;
        read(k);
        int u=0,v;
        for(int j=1;j<=k;j++)
        {
            if(j==1) read(u);
            else
            {
                read(v);
                g[v].push_back(u);
                deg[u]++;
                u=v;
            }
        }
    }

    if(topsort()) puts("Yes");
    else puts("No");
	
    return 0;
}