#include <bits/stdc++.h>
#define _GLIBCXX_DEBUG
using namespace std;
using ll = long long;
using vec = vector<ll>;
using vect = vector<double>;
using Graph = vector<vector<ll>>;
#define loop(i, n) for (ll i = 0; i < n; i++)
#define Loop(i, m, n) for (ll i = m; i < n; i++)
#define pool(i, n) for (ll i = n; i >= 0; i--)
#define Pool(i, m, n) for (ll i = n; i >= m; i--)
#define mod 1000000007ll
//#define mod 998244353ll
#define flagcount __builtin_popcount
#define flag(x) (1ll << x)
#define flagadd(bit, x) bit |= flag(x)
#define flagpop(bit, x) bit &= ~flag(x)
#define flagon(bit, i) bit &flag(i)
#define flagoff(bit, i) !(bit & (1ll << i))
#define all(v) v.begin(), v.end()
#define low2way(v, x) lower_bound(all(v), x)
#define high2way(v, x) upper_bound(all(v), x)
#define idx_lower(v, x) (distance(v.begin(), low2way(v, x)))  //配列vでx未満の要素数を返す
#define idx_upper(v, x) (distance(v.begin(), high2way(v, x))) //配列vでx以下の要素数を返す
#define idx_lower2(v, x) (v.size() - idx_lower(v, x))         //配列vでx以上の要素数を返す
#define idx_upper2(v, x) (v.size() - idx_upper(v, x))         //配列vでxより大きい要素の数を返す
#define putout(a) cout << a << endl
#define Sum(v) accumulate(all(v), 0ll)
#define gcd(x, y) __gcd(x, y)
ll ctoi(char c)
{
    if (c >= '0' && c <= '9')
    {
        return c - '0';
    }
    return -1;
}
template <typename T>
string make_string(T N)
{
    string ret;
    T now = N;
    while (now > 0)
    {
        T x = now % 10;
        ret += (char)('0' + x);
        now /= 10;
    }
    reverse(all(ret));
    return ret;
}
template <typename T>
T lcm(T x, T y)
{
    T z = gcd(x, y);
    return x * y / z;
}
template <typename T>
bool primejudge(T n)
{
    if (n < 2)
        return false;
    else if (n == 2)
        return true;
    else if (n % 2 == 0)
        return false;
    double sqrtn = sqrt(n);
    for (T i = 3; i < sqrtn + 1; i++)
    {
        if (n % i == 0)
        {
            return false;
        }
        i++;
    }
    return true;
}
template <typename T>
bool chmax(T &a, const T &b)
{
    if (a < b)
    {
        a = b; // aをbで更新
        return true;
    }
    return false;
}
template <typename T>
bool chmin(T &a, const T &b)
{
    if (a > b)
    {
        a = b; // aをbで更新
        return true;
    }
    return false;
}
//場合によって使い分ける
//const ll dx[4]={1,0,-1,0};
//const ll dy[4]={0,1,0,-1};
const ll dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
const ll dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};
//2次元配列の宣言
//vector<vector<ll>> field(h, vector<ll>(w));
struct union_find
{
    vector<long long> par;  //親の番号　
    vector<long long> rank; //木の深さ(根のランクは0)
    vector<long long> siz;  //要素xが根なら木の頂点数を格納する
    //初期化子リストを用いた初期化
    union_find(long long N) : par(N), rank(N), siz(N)
    {
        for (long long i = 0; i < N; i++)
        {
            par[i] = i;
            rank[i] = 0;
            siz[i] = 1;
        }
    }
    //要素xが所属する木の根を再帰的に発見する
    long long root(long long x)
    {
        if (par[x] == x)
            return x;
        return par[x] = root(par[x]); //経路圧縮
    }
    //要素xが属する木と要素yが属する木の併合
    void unite(long long x, long long y)
    {
        long long rx = root(x);
        long long ry = root(y);
        if (rx == ry)
            return; //同じ木に属してたらそのまま
        if (rank[rx] < rank[ry])
        {
            par[rx] = ry; //根がryの木に併合
            siz[ry] = siz[rx] + siz[ry];
        }
        else
        {
            par[ry] = rx; //根がrxの木に併合
            siz[rx] = siz[rx] + siz[ry];
            if (rank[rx] == rank[ry])
                rank[rx]++;
        }
    }
    //要素xが属する木と要素yが属する木が同じならtrueを返す
    bool same(long long x, long long y)
    {
        return root(x) == root(y);
    }
    //要素xが属する木の頂点数を返す
    long long size(long long x)
    {
        return siz[root(x)];
    }
};
//union-find木による森がいくつの木からなるかを返す
long long partial(union_find tree)
{
    long long n = tree.siz.size();
    vector<bool> seen(n, false);
    long long ans = 0;
    for (long long i = 0; i < n; i++)
    {
        if (seen[tree.root(i)])
            continue;
        seen[tree.root(i)] = true;
        ans++;
    }
    return ans;
}
int main()
{
    cout << fixed << setprecision(30);
    ll N, M;
    cin >> N >> M;
    union_find tree(N);
    loop(i, M)
    {
        ll a, b;
        cin >> a >> b;
        a--;
        b--;
        tree.unite(a, b);
    }
    ll maxx = 0;
    loop(i, N) maxx = max(maxx, tree.size(i));
    putout(maxx);
    return 0;
}


Measured memory_bytes: 7948