import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;

public class Main {
    public static void main(String[] args) {
        long timeStart = System.nanoTime();
        Utility.FastReader fr = new Utility.FastReader();
        Solver solver = new Solver(fr);
        int t = 1;
        while (t-- > 0) {
            solver.solve();
        }
        long timeEnd = System.nanoTime();
//        System.out.println("Completed in :" + ((double) (timeEnd - timeStart) / 1000000) + " miliseconds");
    }

    static class Solver {
        Utility.FastReader fr;
        static int[] parent;
        static int[] nComponents;

        public Solver(Utility.FastReader fr) {
            this.fr = fr;
        }

        void makeSet(int node){
            parent[node]=node;
            nComponents[node]=1;
        }

        int findSet(int node){
            if(node==parent[node]) return node;
            return parent[node]=findSet(parent[node]);
        }

        void unionSets(int a, int b){
            a=findSet(a);
            b=findSet(b);
            if(a!=b){
                parent[a]=b;
                nComponents[b]+=nComponents[a];
            }
        }

        void solve() {
            int n=fr.nextInt(), m=fr.nextInt();
            parent=new int[n+1];
            nComponents=new int[n+1];
            Arrays.fill(parent, -1);
            int u, v;
            for(int i=0; i<m; ++i){
                u=fr.nextInt(); v=fr.nextInt();
                if(parent[u]==-1)
                    makeSet(u);
                if(parent[v]==-1)
                    makeSet(v);
                u=findSet(u);
                v=findSet(v);
                unionSets(u, v);
            }
            Set<Integer> roots=new HashSet<>();
            for(int i=1; i<=n; ++i){
                if(parent[i]!=-1){
                    roots.add(parent[i]);
                }
            }
            int mxComponent=1;
            for(int node: roots){
                mxComponent=Math.max(mxComponent, nComponents[node]);
            }
            System.out.println(mxComponent);


        }
    }

    static class Utility {
        static void sort(int[] a) {
            ArrayList<Integer> list = new ArrayList<>();
            for (int i : a) list.add(i);
            Collections.sort(list);
            for (int i = 0; i < a.length; i++) a[i] = list.get(i);
        }

        static void shuffleArray(long[] arr) {
            int n = arr.length;
            Random rnd = new Random();
            for (int i = 0; i < n; ++i) {
                long tmp = arr[i];
                int randomPos = i + rnd.nextInt(n - i);
                arr[i] = arr[randomPos];
                arr[randomPos] = tmp;
            }
        }

        static void shuffleArray(int[] arr) {
            int n = arr.length;
            Random rnd = new Random();
            for (int i = 0; i < n; ++i) {
                int tmp = arr[i];
                int randomPos = i + rnd.nextInt(n - i);
                arr[i] = arr[randomPos];
                arr[randomPos] = tmp;
            }
        }

        static int gcd(int a, int b) {
            if (b == 0)
                return a;
            return gcd(b, a % b);
        }

        static long gcd(long a, long b) {
            if (b == 0)
                return a;
            return gcd(b, a % b);
        }

        static class FastReader {
            BufferedReader br;
            StringTokenizer st;

            public FastReader() {
                br = new BufferedReader(new
                        InputStreamReader(System.in));
            }

            String next() {
                while (st == null || !st.hasMoreElements()) {
                    try {
                        st = new StringTokenizer(br.readLine());
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                return st.nextToken();
            }

            int nextInt() {
                return Integer.parseInt(next());
            }

            long nextLong() {
                return Long.parseLong(next());
            }

            double nextDouble() {
                return Double.parseDouble(next());
            }

            String nextLine() {
                String str = "";
                try {
                    str = br.readLine();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                return str;
            }
        }
    }
}



Measured memory_bytes: 59908