#include <iostream>
#include<stdio.h>
#include<vector>
#include<queue>
#include <fstream>

using namespace std;
//implementarea de la seminar
ifstream f("dfs.in");
ofstream o("dfs.out");
vector<int> graph[100005];
char viz[100005];
int n, m, answer;

void dfs(int node) {
    if(viz[node])
        return ;
    viz[node] = 1;
    for(auto vecin : graph[node]) {
        dfs(vecin);
    }
}

int main() {
    int a, b;
   f>>n>>m;
    for(int i = 1; i <= m; i++) {
        f>>a>>b;
        graph[a].push_back(b);
        graph[b].push_back(a);   //retinem graful transpus
    }

    for(int i = 1; i <= n; i++) {
        if(!viz[i]) {
            dfs(i);
            answer++;
        }
    }

   o<<answer;

    return 0;
}