/*
Author : Chandan Agrawal
College : Poornima College of Engg. jaipur, Raj
Mail : chandanagrawal23@gmail.com
" when you are not practicing someone else is ,
 and the day u meet them u will lose "
*/
#include<bits/stdc++.h>
#include<stdio.h>
using namespace std;

#define fastio ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define MAX 200005

#define ll long long
#define ld long double
#define lli  int

#define pb push_back
#define INF 1000000000000
#define mod 1000000007

// trignometric function always give value in Radians only
#define PI acos(-1) //3.1415926535897932384626433832795028
#define dsin(degree) sin(degree*(PI/180.0))
#define dcos(degree) cos(degree*(PI/180.0))
#define dtan(degree) tan(degree*(PI/180.0))

#define rsin(radian) sin(radian)
#define rcos(radian) cos(radian)
#define rtan(radian) tan(radian)

#define mem0(a) memset(a,0,sizeof(a))
#define mem1(a) memset(a,-1,sizeof(a))
#define memf(a) memset(a,false,sizeof(a))

#define loop(i,n)  for (lli i = 0; i < n; i++)
#define FOR(i,a,b) for (lli i = a; i < b; i++)

#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define makeuniq(v) v.resize(unique(all(v)) - v.begin()); //only uniq element in vector after this
#define sz(x) int(x.size())
#define F first
#define S second

#define mii map<lli,lli>

#define pii pair<lli,lli>

#define vi vector<lli>
#define vvi vector<vi>
#define vpi vector<pii>
#define vbool vector<bool>

#define seti set<lli>

#define gcd(a,b) __gcd((a),(b))
#define lcm(a,b) (a/gcd(a,b))*b
#define abs(x) ((x < 0)?-(x):x)

#define endl '\n'

template <typename Head>
void print(Head&& head)
{
    cout<<head<<endl;
}
template <typename Head, typename... Tail>
void print(Head&& head, Tail... tail)
{
    cout<<head<<" ";
    print(tail...);
}

#define scanarr(a,n) for(lli i=0;i<n;i++)    cin>>a[i];
#define scanvec(a,n) for(lli i=0;i<n;i++){ lli x ; cin>>x; a.pb(x);}

#define printarr(a,n) for(lli i=0;i<n;i++)   cout<<a[i]<<" "; cout<<endl;
#define printvec(vec) for(auto xt : vec) cout<<xt<<" ";    cout<<"\n";

#define FD(N) fixed<<setprecision(N)

#define deb(x) cout<<#x<<" "<<x<<endl;

/*
1D vector -  vi dp(n,value);
2D vector -  vvi dp(n,vi(n,value));
*/

// chandan1,2
void chandan1(){int y=1;return;}
void chandan2(){
        loop(i,10){
        lli x=1;
    }
    return(chandan1());
}

//-------------------------------------------------------------------DSU---------------------------------------------------------------

struct DSU
{
    static const int MAXN=200005;
	lli parent[MAXN];
    lli size[MAXN];
    
    //initialize all structures
    void init(lli n)
    {
        loop(i,n)
        {
            parent[i]=i;
            size[i]=1;
        }
    }
    
    // return the root(parent) of i (log *n) 
    lli root(lli i)
    {
        while(parent[i]!=i)
        {
            parent[i] = parent[parent[i]];
            i = parent[i];
        }
        return i;
    }
    
    
    // union of two nodes using path compression
    void Union(lli a , lli b)
    {
        lli root_a = root(a);
        lli root_b = root(b);
        
        if(root_a == root_b) return; // why we increase size then ?
        
        if(size[root_a] < size[root_b])
        {
            parent[root_a] = parent[root_b];
            size[root_b] += size[root_a];
        }
        
        else
        {
            parent[root_b] = parent[root_a];
            size[root_a] += size[root_b];
        }
    }
    
    // check whether a and b are in same set (both have same root)
    bool find(lli a , lli b)
    {
        return(a==b or root(a) == root(b));
    }

};


//-------------------------------------------------------------------DSU---------------------------------------------------------------

//https://codeforces.com/contest/505/problem/B
int main(){
fastio
lli t=1;
//cin>>t;
chandan2();
while(t--) {
    lli n,m,q;
    cin>>n>>m;
    DSU uf;
    uf.init(n+5);
    loop(i,m)
    {
        lli x,y;
        cin>>x>>y;
        uf.Union(x,y);
    }
    lli maxi = -1;
    FOR(i,1,n+1)
        maxi = max(maxi ,uf.size[uf.root(i)]);
    print(maxi);
   
  }
return 0;
}

Measured memory_bytes: 5220