#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

void dfs(int node, vector<vector<int>>& graph, vector<bool>& visited) {
    visited[node] = true; 

    for (int neighbor : graph[node]) {
        if (!visited[neighbor]) { 
            dfs(neighbor, graph, visited); 
        }
    }
}

int main() {
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");

    int N, M;
    fin >> N >> M;

    vector<vector<int>> graph(N + 1);
    for (int i = 0; i < M; i++) {
        int x, y;
        fin >> x >> y;
        graph[x].push_back(y);
        graph[y].push_back(x); 
    }

    vector<bool> visited(N + 1, false); 
    int components = 0; 

    for (int i = 1; i <= N; i++) {
        if (!visited[i]) {
            dfs(i, graph, visited);
            components++; 
        }
    }
    fout << components << endl;

    fin.close();
    fout.close();
    return 0;
}