// Slower C++ solution:
//Bismillahir Rahmanir Rahim

 

//#pragma GCC optimize("Ofast,unroll-loops")

//#pragma GCC target("avx,avx2,fma")

        

#include<bits/stdc++.h>

#include<ext/pb_ds/assoc_container.hpp>

#include<ext/pb_ds/tree_policy.hpp>

 

#define ll long long

#define ull unsigned long long

#define pii pair<int,int>

#define pll pair<ll,ll>

#define xx first

#define yy second

#define sci(n) scanf("%d",&n)

#define scii(n,m) scanf("%d%d",&n,&m)

#define sciii(n,m,w) scanf("%d%d%d",&n,&m,&w)

#define scl(n) scanf("%lld",&n)

#define scll(n,m) scanf("%lld%lld",&n,&m)

#define sclll(n,m,w) scanf("%lld%lld%lld",&n,&m,&w)

#define pf(a)   printf("%d\n",a)

#define CASE(a) printf("Case %d: ",a)

#define endl '\n'

#define READ  freopen("input.txt","r",stdin)

#define WRITE freopen("output.txt","w",stdout);

#define PI acos(-1)

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

#define SQR(a) (a)*(a)

#define all(v) v.begin(),v.end()

#define pb push_back

#define pri priority_queue<int>

#define rev_pri priority_queue<int,vector<int>,greater<int> >

#define IOS ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);

#define mod 1000000007

#define inf INT_MAX

#define eps 1e-9

 

using namespace __gnu_pbds;

using namespace std;



#define error(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }



void err(istream_iterator<string> it) {}

template<typename T, typename... Args>

void err(istream_iterator<string> it, T a, Args... args) {

  cerr << *it << " = " << a << endl;

  err(++it, args...);

}

 

//int dx[] = {0,1,0,-1,1,1,-1,-1};

//int dy[] = {1,0,-1,0,1,-1,-1,1};

 

//ll ncr(ll n,ll r){if(n==r)return 1;if(r==1)return n;if(dp[n][r]!=-1)return dp[n][r];return dp[n][r]=ncr(n-1,r)+ncr(n-1,r-1);}

 

// bit manipulations

 

//bool checkbit(int mask,int bit){return mask & (1<<bit);}

//int setbit(int mask,int bit){ return mask | (1<<bit) ; }

//int clearbit(int mask,int bit){return mask & ~(1<<bit);}

//int togglebit(int mask,int bit){return mask ^ (1<<bit);}

//int bitno(int mask) {return (int)__builtin_popcount(mask);}

 

template <typename T> T BigMod (T b,T p,T m){if (p == 0) return 1;if (p%2 == 0){T s = BigMod(b,p/2,m);return ((s%m)*(s%m))%m;}return ((b%m)*(BigMod(b,p-1,m)%m))%m;}

template <typename T> T ModInv (T b,T m){return BigMod(b,m-2,m);}

template <typename T> T POW(T B,T P){ if(P==0) return 1; if(P&1) return B*POW(B,P-1);  else return SQR(POW(B,P/2));}

template <typename T> T Dis(T x1,T y1,T x2, T y2){return sqrt( SQR(x1-x2) + SQR(y1-y2) );}

template <typename T> T Angle(T x1,T y1,T x2, T y2){ return atan( double(y1-y2) / double(x1-x2));}

template <typename T> T gcd(T a,T b){if(a<0)return gcd(-a,b);if(b<0)return gcd(a,-b);return (b==0)?a:gcd(b,a%b);}

template <typename T> T lcm(T a,T b) {if(a<0)return lcm(-a,b);if(b<0)return lcm(a,-b);return a*(b/gcd(a,b));}

template <typename T> T euclide(T a,T b,T &x,T &y) {if(a<0){T d=euclide(-a,b,x,y);x=-x;return d;}   if(b<0){T d=euclide(a,-b,x,y);y=-y;return d;}   if(b==0){x=1;y=0;return a;}else{T d=euclide(b,a%b,x,y);T t=x;x=y;y=t-(a/b)*y;return d;}}

template <typename T> void ia (T a[],int n){for (int i=0; i<n; i++) cin >> a[i];}

template <typename T> void pa (T a[],int n){for (int i=0; i<n-1; i++) cout << a[i] << " ";cout << a[n-1] << endl;}

template <typename T> ll isLeft(T a,T b,T c) { return (a.x-b.x)*(b.y-c.y)-(b.x-c.x)*(a.y-b.y);}

 

template<typename T>

using ordered_set=tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;

 

///********************************MY CODE STARTS HERE********************************///

 

 

#define mxn 200005

int cnt;

vector<int> adj[mxn];

bool vis[mxn];

void dfs(int u){

    

    cnt++;

	vis[u] = true;



	for(auto v : adj[u]){

		if(!vis[v])dfs(v);

	}

	

}

 

void solve(){

 

    int n , m;

    cin >> n >> m;



    for(int i = 0;i < m;i++){

    	int u , v;

    	cin >> u >> v;

    	adj[u].pb(v);

    	adj[v].pb(u);

    }



    int ans = 0;

    for(int i = 1;i <= n;i++){

    	if(!vis[i]){

    		cnt = 0;

    		dfs(i);

    		ans= max(ans , cnt);

    	}

    }



    cout << ans << endl;

}



 

 

int main(){

       IOS;

    

    int T = 1;

    // cin >> T;

    while(T--){

        solve();

    }

 

return 0;

}

// Faster C++ solution for the same problem (measured speedup: 6.51278308510649x):
#include <bits/stdc++.h>

 

using namespace std;



// traduções



// even -> par

// odd -> impar

// west -> oeste



typedef long long ll;

typedef pair<int, int> ii;

typedef vector<ii> vii;

typedef vector<int> vi;



#define INF 1000000000

#define MOD 1000000007

#define EPS 1e-12

const double PI = acos(-1.0);



#define REP(i, a, b) for(int i = (a); i < (b); ++i)

#define ALL(x) x.begin(), x.end()

#define UNIQUE(c) (c).resize(unique(ALL(c)) - (c).begin())

#define FILL(a,v) memset(a, v, sizeof a)



// bitmask operations

#define SETBIT(S, j) S |= (1 << j)

#define CLEARBIT(S, j) S &= ~(1 << j)

#define ISSET(S, j) S & (1 << j)

#define FLIPBIT(S, j) S ^= (1 << j)

#define LSBIT(S) (S & (-S))



// debug

#define DEBUGSTR(S) cout << "(" << S << ")\n";



int tranform(int i, int j, int M) {

    return j + M*i;

}



class UFDS {

private:

    vi size, ps;

    int numSets;



public:

    UFDS(int N) : size(N + 1, 1), ps(N + 1), numSets(N) {

        iota(ps.begin(), ps.end(), 0);

    }



    int find_set(int x) {

        return x == ps[x] ? x : (ps[x] = find_set(ps[x]));

    }



    bool same_set(int x, int y) {

        return find_set(x) == find_set(y);

    }



    int getMax() {

        int maior = -1;

        int sz = size.size();

        for(int i = 0; i < sz; ++i)

            maior = max(maior, sizeOfSet(i));

        

        return maior;

    }



    int sizeOfSet(int i) { return size[find_set(i)]; }



    int numDisjointSets() const { return numSets; }



    void union_set(int x, int y) {

        int p = find_set(x), q = find_set(y);



        if(p == q)

            return;

        

        numSets--;



        if (size[p] < size[q])

            swap(p, q);



        ps[q] = p;



        size[p] += size[q];

    }

};



int main() {

    //ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);

    int N, M;

    scanf(" %d %d", &N, &M);



    UFDS UF(N);



    REP(i, 0, M) {

        int a, b;

        scanf(" %d %d", &a, &b);



        UF.union_set(a, b);

    }



    printf("%d\n", UF.getMax());



    return 0;

}