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

using namespace std;

void dfs(vector<vector<int>> graph, vector<bool> &isVisited, int node){
    isVisited[node] = 1;
    for(int neighbour : graph[node]){
        if(!isVisited[neighbour]){
            dfs(graph, isVisited, neighbour);
        }
    }
}

int main(){
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");
    const int Nmax = 100005;
    int n, m;
    fin >> n >> m;
    vector<vector<int>> graph(n+1, vector<int>());
    for(int i = 1; i <= m; i++){
        int x, y;
        fin >> x >> y;
        graph[x].push_back(y);
        graph[y].push_back(x);
    }
    int sol = 0;
    vector<bool> isVisited(n+1);
    for(int i = 1; i <= n; i++){
        if(!isVisited[i]){
            sol++;
            dfs(graph, isVisited, i);
        }
    }
    fout << sol;
    return 0;
}