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

// template {{{
#define  range(i, l, r) for (int i = (int)(l); i < (int)(r); (i) += 1)
#define rrange(i, l, r) for (int i = (int)(r) - 1; i >= (int)(l); (i) -= 1)

#define  whole(f, x, ...) ([&](decltype((x)) container) { return (f)(  begin(container),  end(container), ## __VA_ARGS__); })(x)
#define rwhole(f, x, ...) ([&](decltype((x)) container) { return (f)( rbegin(container), rend(container), ## __VA_ARGS__); })(x)

#define debug(x) cerr << "(" << __LINE__ << ")" << #x << ": " << (x) << endl

using i32 = int;
using u32 = unsigned int;
using i64 = long long;
using u64 = unsigned long long;

// constexpr i32 mod   = 998244353;
constexpr i32 mod   = 1e9 + 7;
constexpr i32 inf   = 1001001001;
constexpr i64 infll = 1001001001001001001ll;

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

struct IoSetup { IoSetup(int x = 15){ cin.tie(0); ios::sync_with_stdio(0); cout << fixed << setprecision(x); cerr << fixed << setprecision(x); } } iosetup;

template <typename T = i64> T input() { T x; cin >> x; return x; }

template <typename T> ostream &operator<<(ostream &os, vector<T> &v) { range(i, 0, v.size()) { os << v[i] << (i + 1 != v.size() ? " " : ""); } return os; }
template <typename T> istream &operator>>(istream &is, vector<T> &v) { for (T &in : v) is >> in; return is; }

template <typename T1, typename T2> ostream &operator<<(ostream &os, pair<T1, T2> p) { os << "(" << p.first << ", " << p.second << ")"; return os; }
template <typename T1, typename T2> istream &operator>>(istream &is, pair<T1, T2> &p) { is >> p.first >> p.second; return is; }

template <typename T> vector<T> make_vector(size_t a, T b) { return vector<T>(a, b); }
template <typename... Ts> auto make_vector(size_t a, Ts... ts) { return vector<decltype(make_vector(ts...))>(a, make_vector(ts...)); }

template <typename T1, typename T2> inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }
template <typename T1, typename T2> inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); }
// }}}

// union find {{{
class union_find {

    using data_type = int_fast32_t;
    std::vector< data_type > data_;

    public:
    union_find(std::size_t size) : data_(size, -1) {}

    std::size_t size() const {
        return data_.size();
    }

    data_type get_root(data_type x) {
        return (data_[x] < 0 ? x : data_[x] = get_root(data_[x]));
    }

    bool is_root(data_type x) {
        return x == get_root(x);
    }

    bool is_same(data_type x, data_type y) {
        return get_root(x) == get_root(y);
    }

    void unite(data_type x, data_type y) {
        x = get_root(x); y = get_root(y);
        if (x == y) return;

        if (data_[x] > data_[y]) std::swap(x, y);
        data_[x] += data_[y];
        data_[y] = x;
    }

    data_type element_count(data_type x) {
        return -data_[get_root(x)];
    }
};
// }}}

void solver() {
    int n = input(), m = input();
    union_find uf(n);
    range(i, 0, m) {
        int u = input() - 1, v = input() - 1;
        uf.unite(u, v);
    }

    int ans = 0;
    range(i, 0, n) {
        chmax(ans, uf.element_count(i));
    }

    cout << ans << endl;
}

signed main(int argc, char *argv[]) {
    solver();
}


Measured memory_bytes: 4764