#include<cstdio>
#include<iostream>
#include<cstring>
#include<string>
#include<cmath>
#include<algorithm>
#include<vector>
#include<map>
#include<set>
#include<queue>
using namespace std;
typedef long long ll;
const int maxn = 1e5 + 10;
const int inf = 0x3f3f3f3f;
const ll mod = 1e9 + 7;

/*
int n;
ll sum[1001];

int main()
{
	while(scanf("%d", &n) != EOF)
	{
		int flag = 1;
		ll ans = 0;
		for(int i = 1; i <= n; i++)
		{
			scanf("%lld", &sum[i]);
			if(flag)
			{
				if(sum[i] == 1)
					ans++;
				else 
					flag = 0;
			}
		}
		if(flag != 1)
		{
			if(ans % 2)
				cout << "L" << endl;
			else 
				cout << "H" << endl;
		}
		else 
		{
			if(ans % 2)
				cout << "H" << endl;
			else 
				cout << "L" << endl;
		}
	}
	return 0;
}*/

int n, m;
ll sum[maxn];
int fa[maxn];
int flag[maxn];

int find(int x)
{
	if(x == fa[x])
		return x;
	else 
		return fa[x] = find(fa[x]);
}

int main()
{
	while(~scanf("%d %d", &n, &m))
	{
		for(int i = 1; i <= n; i++)
		{
			fa[i] = i;
			sum[i] = 0;
			flag[i] = 0;
		}
		while(m--)
		{
			int u, v;
			scanf("%d %d", &u, &v);
			flag[u] = 1;
			flag[v] = 1;
			int fx = find(u), fy = find(v);
			if(fx != fy)
				fa[fx] = fy;
		}
		ll s = 0;
		for(int i = 1; i <= n; i++)
		{
			if(flag[i] == 0)
				continue;
			sum[find(i)]++;
		}
		sort(sum + 1, sum + 1 + n);
		cout << sum[n] << endl;
	}
	return 0;
}