/**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author
 */

#include <iostream>
#include <fstream>

#include <iostream>
#include "bits/stdc++.h"

using namespace std;

typedef unsigned long long ll;
typedef int                     integer;
#define int                     long long
#define ii                      pair<int,int>
#define vii                     vector<pair<int,int>>
#define vi                      vector<int>
#define vvi                     vector<vector<int>>
#define f(a,b,c)                for(int a=(b);a<(c);a++)
#define s(x)                    in>>x
#define s2(x,y)                 in>>x>>y
#define s3(x,y,z)               in>>x>>y>>z
#define s4(x,y,z,w)             in>>x>>y>>z>>w
#define p(x)                    out<<(x)<<endl
#define p2(x,y)                 out<<(x)<<" "<<(y)<<endl
#define pl(x)                   out<<(x)
#define p2l(x,y)                out<<(x)<<" "<<(y)
#define p1d(a,n)                for(int ix=0;ix<(n);ix++) out<<a[ix]<<" "; out<<endl
#define p2d(a,n,m)              for(int ix=0;ix<(n);ix++){ for(int jx=0;jx<(m);jx++) out<<a[ix][jx]<<" "; out<<endl;}
#define range(v)                v.begin(),v.end()
#define w(x)                    while(x--)
#define rst(x)                  memset(x, -1, sizeof(x))
#ifndef ATCODER_DSU_HPP
#define ATCODER_DSU_HPP 1

#include <algorithm>
#include <cassert>
#include <vector>

namespace atcoder {

// Implement (union by size) + (path compression)
// Reference:
// Zvi Galil and Giuseppe F. Italiano,
// Data structures and algorithms for disjoint set union problems
struct dsu {
  public:
    dsu() : _n(0) {}
    dsu(int n) : _n(n), parent_or_size(n, -1) {}

    int merge(int a, int b) {
        assert(0 <= a && a < _n);
        assert(0 <= b && b < _n);
        int x = leader(a), y = leader(b);
        if (x == y) return x;
        if (-parent_or_size[x] < -parent_or_size[y]) std::swap(x, y);
        parent_or_size[x] += parent_or_size[y];
        parent_or_size[y] = x;
        return x;
    }

    bool same(int a, int b) {
        assert(0 <= a && a < _n);
        assert(0 <= b && b < _n);
        return leader(a) == leader(b);
    }

    int leader(int a) {
        assert(0 <= a && a < _n);
        if (parent_or_size[a] < 0) return a;
        return parent_or_size[a] = leader(parent_or_size[a]);
    }

    int size(int a) {
        assert(0 <= a && a < _n);
        return -parent_or_size[leader(a)];
    }

    std::vector<std::vector<int>> groups() {
        std::vector<int> leader_buf(_n), group_size(_n);
        for (int i = 0; i < _n; i++) {
            leader_buf[i] = leader(i);
            group_size[leader_buf[i]]++;
        }
        std::vector<std::vector<int>> result(_n);
        for (int i = 0; i < _n; i++) {
            result[i].reserve(group_size[i]);
        }
        for (int i = 0; i < _n; i++) {
            result[leader_buf[i]].push_back(i);
        }
        result.erase(
            std::remove_if(result.begin(), result.end(),
                           [&](const std::vector<int>& v) { return v.empty(); }),
            result.end());
        return result;
    }

  private:
    int _n;
    // root node: -1 * component size
    // otherwise: parent
    std::vector<int> parent_or_size;
};

}  // namespace atcoder

#endif  // ATCODER_DSU_HPP


void ssolve(std::istream& in, std::ostream& out){
    int n, m;
    s2(n, m);

    atcoder::dsu dsu = atcoder::dsu(n);
    f(i,0,m) {
        int u,v;
        s2(u,v);

        u--, v--;

        dsu.merge(u,v);

    }
    int c = 0;

    for(const auto& g: dsu.groups()) {
        c = max(c,(int)g.size());
    }
    out<<c<<endl;
}

class DFriends {
public:
	void solve(std::istream& in, std::ostream& out) {
        ios_base::sync_with_stdio(false);
        in.tie(0);out.tie(0);
        int t;
        int READ = 0;
        if(READ) s(t);
        else t = 1;
        while(t--){
            ssolve(in, out);
        }
	}
};


integer main() {
	DFriends solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	solver.solve(in, out);
}


Measured memory_bytes: 18604