#include <iostream>
#include <vector>
#include <deque>
#include <algorithm>
#include <numeric>
#include <string>
#include <cstring>
#include <list>
#include <unordered_set>
#include <tuple>
#include <cmath>
#include <limits>
#include <type_traits>
#include <iomanip>
#include <map>
#include <unordered_map>
#include <queue>
#include <stack>
#include <set>
#include <bitset>
#include <complex>
#include <regex>
#include <random>
using namespace std;

#define rep(i,n)	for(lint i = 0; i < n; i++)
#define repr(i,n)	for(lint i = n - 1; i >= 0; i--)
#define repi(i,ini,n)	for(lint i = ini; i < n; i++)
#define repir(i,ini,n)	for(lint i = n-1; i >= ini; i--)
#define repb(i,start,end)	for(lint i = start; i <= end; i++)
#define repbr(i,start,end)	for(lint i = end; i >= start; i--)

#define bit(n)				(1LL << (n))

#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define rg(v, ini, end) v.begin() + ini, v.begin()+end

#define ret return 0;
#define chmax(a, b) a=max(a,b)
#define chmin(a, b) a=min(a,b)

using lint = long long;
using ulint = unsigned long long;
using ld = long double;
struct xy
{
	lint x, y;
	xy() :x(0), y(0) {}
	xy(lint _x, lint _y) : x(_x), y(_y) {}
	xy operator+(const xy& p) const
	{
		return xy(x + p.x, y + p.y);
	}
	bool operator<(xy p) const
	{
		if (y == p.y)
			return x < p.x;
		return y < p.y;
	}
};
struct xyd
{
	ld x, y;
	xyd() :x(0), y(0) {}
	xyd(long double _x, long double _y) : x(_x), y(_y) {}
};
using vec = vector<lint>;
using vecd = vector<ld>;
using vecs = vector<string>;
using vecp = vector<xy>;
template<class T> using vect = vector<T>;
class vec2 : public vector<vector<lint>>
{
public:
	vec2() {}
	vec2(lint n) : vector(n) {}
	vec2(lint h, lint w) : vector(h, vector<lint>(w)) {}
	vec2(lint h, lint w, lint v) : vector(h, vector<lint>(w, v)) {}
};

template<class T> using priq = priority_queue<T>;
template<class T> using rpriq = priority_queue<T, vector<T>, greater<T>>;
template<class Key, class Val> using hashmap = unordered_map<Key, Val>;
template<class Key> using hashset = unordered_set<Key>;

template<class It>
constexpr typename It::value_type rmax(It begin, It end) {
	return *max_element(begin, end);
}

template<class T1, class T2>
constexpr auto mmax(T1 arg1, T2 arg2) {
	using T = decltype(arg1 + arg2);
	return max(T(arg1), T(arg2));
}

template<class T, class ...Types>
constexpr auto mmax(T arg0, Types ...args) {
	return mmax(arg0, mmax(args...));
}

template<class It>
constexpr typename It::value_type rmin(It begin, It end) {
	return *min_element(begin, end);
}

template<class T1, class T2>
constexpr auto mmin(T1 arg1, T2 arg2) {
	using T = decltype(arg1 + arg2);
	return min(T(arg1), T(arg2));
}

template<class T, class ...Types>
constexpr auto mmin(T arg0, Types ...args) {
	return mmin(arg0, mmin(args...));
}

mt19937 mtrand((random_device())());

const double pi = 3.141592653589793238462;
const lint intmax = 9223372036854775807;
const lint inf = 1100100100100100100LL;

constexpr lint div2(lint p, lint q)
{
	return (p + q - 1) / q;
}

#if(__cplusplus < 201703L)

lint gcd(lint a, lint b) {
	while (1) {
		if (a < b) swap(a, b);
		if (!b) break;
		a %= b;
	}
	return a;
}

lint lcm(lint a, lint b)
{
	return a / gcd(a, b) * b;
}

#endif

template<class T>
struct nval {
	lint n;		// counts
	T val;
	nval() : n(0) {};
	nval(lint _n, T _val) : n(_n), val(_val) {};
};

template<class It, class It2>
auto spacel(It i, It2 end)
{
	if (i + 1 == end)
	{
		return '\n';
	}
	else
	{
		return ' ';
	}
}

ostream& setp(ostream& ost)
{
	cout << setprecision(60) << fixed;
	return ost;
}

const ulint mod = 1000000007;
//const ulint mod = 998244353;
const ld eps = 0.0000001;


struct mint
{
	lint n;
	mint() :n(0) {}
	mint(lint a) {
		if (a < 0)
			n = mod - ((-a) % mod);
		else
			n = a % mod;
	}
	mint& operator+=(mint a) {
		n += a.n;
		n %= mod;
		return *this;
	}
	mint& operator-=(mint a) {
		n += mod;
		n -= a.n;
		n %= mod;
		return *this;
	}
	mint& operator*=(mint a) {
		n *= a.n;
		n %= mod;
		return *this;
	}
	mint& operator%=(mint a) {
		n %= a.n;
		return *this;
	}
	mint& operator++() {
		n++;
		n %= mod;
		return *this;
	}
	mint& operator--() {
		n += mod;
		n--;
		n %= mod;
		return *this;
	}
};

mint operator+(mint a, mint b) {
	a += b;
	return a;
}
mint operator-(mint a, mint b) {
	a -= b;
	return a;
}
mint operator*(mint a, mint b) {
	a *= b;
	return a;
}

vector<mint> invtbl;
vector<mint> finvtbl;
vector<mint> facttbl;

mint factMod(lint n) {
	if (n == 0)
		return 1;
	mint ans = 1;
	while (n > 1) {
		ans *= n;
		n--;
	}
	return ans;
}
mint powMod(mint x, lint y)
{
	if (x.n <= 1)
		return x;
	if (y == 0)
		return 1;
	else if (y == 1)
		return x;
	else {
		mint tmp = powMod(x, y / 2);
		if (y % 2 == 0)
			return tmp * tmp;
		else
			return tmp * tmp * x;
	}
}
mint modinv(mint n) {
	return powMod(n, mod - 2);
}

void preCalcInv(lint up) {
	invtbl.resize(up + 1);
	invtbl[1] = 1;
	repb(a, 2, up)
		invtbl[a] = invtbl[a] = mod - invtbl[mod % a] * (mod / a);
}

mint operator/(mint a, mint b) {
	if (b.n < invtbl.size())
		a *= invtbl[b.n];
	else
		a *= modinv(b);
	return a;
}
mint& operator/=(mint& a, mint b) {
	a = a / b;
	return a;
}


struct uf
{
	vector<lint> p;
	vector<lint> s;

	uf(lint n) : p(n), s(n)
	{
		rep(i, n)
		{
			p[i] = i;
			s[i] = 1;
		}
	}

	lint rt(lint n)
	{
		return p[n] == n ? n : p[n] = rt(p[n]);
	}

	void un(lint n, lint m)
	{
		if (rt(n) != rt(m))
		{
			s[rt(m)] += s[rt(n)];
			p[rt(n)] = rt(m);
		}
	}

	bool eq(lint n, lint m)
	{
		return rt(n) == rt(m);
	}

	lint sz(lint n)
	{
		return s[rt(n)];
	}
};


int main()
{
	lint n, m;
	cin >> n >> m;

	uf t(n);

	rep(i, m)
	{
		lint a, b;
		cin >> a >> b;
		a--; b--;
		t.un(a, b);
	}

	lint a = 0;
	rep(i, n)
	{
		chmax(a, t.sz(i));
	}

	cout << a << endl;

	return 0;
}


Measured memory_bytes: 11884