DisjointSet

#include <iostream>

using namespace std;

int counting = 0;

class Node{
public:
    int value;
    Node* ptr;
    Node(int value) : value(value) {
        ptr = this;
    }
};

Node* makeSet(int value){
    Node* newNode = new Node(value);
        return newNode;
}

Node* FindSet(Node* x){
    if(x -> value == x->ptr->value)
        return x;
    else
        return FindSet(x->ptr);
}

void Union(Node* x, Node* y){
    FindSet(y)->ptr = FindSet(x);
}



int main(){

    int n;
    int m;
    Node* root;

    int x, y;

    cin >> n >> m;

    Node* arr[n+1];
    Node* carr[n+1];
    int gk[n+1];

    for(int i = 1; i <= n; i++){
        arr[i] = makeSet(i);
    }

    for(int i = 0; i < m; i++){
        cin >> x >> y;
        Union(arr[x], arr[y]);
    }

    for(int i = 1; i <=n; i++){
        gk[i] = 0;
        carr[i] = FindSet(arr[i]);
    }

    for(int i = 1; i <=n; i++){
        gk[carr[i] -> value]++;
    }

    int max = gk[1];


    for(int i = 2; i <=n; i++){
        if(max < gk[i])
            max = gk[i];
    }

    cout << max;

    return 0;
}