#include <bits/stdc++.h>
using namespace std;
int find_root(int x, vector<int> &p){
	if(p[x] == -1) return x;
	else{
		p[x] = find_root(p[x], p);
		return p[x];
	}
}
signed main(){
	ios::sync_with_stdio(false);
	int n, m;
 
	while(cin >> n >> m){
		int mx = 1;
		vector<int> I_am_your_father(n, -1);
		vector<int> len(n, 1); 
		for(int i = 0; i < m; i++){
			int a, b;
			cin >> a >> b;
			int root_a = find_root(a, I_am_your_father);
			int root_b = find_root(b, I_am_your_father);
			if(root_a != root_b){
				len[root_a] += len[root_b];
				I_am_your_father[root_b] = root_a; 
				mx = max(mx, len[root_a]);
			}
		}
		// for(int i = 0; i < n; i++){
		// 	cout << I_am_your_father[i] << " ";
		// }cout << endl; 
		cout << mx << endl; 
 
 
 
	}
}

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