#include <iostream>
#include <fstream>
#include <bits/stdc++.h>

using namespace std;

ifstream f("dfs.in");
ofstream g("dfs.out");

vector<int> v[100010];
int a,b,N,M;
bitset<100010> viz;

void dfs(int node){
    viz[node] = true;
    for(auto it: v[node])
        if(!viz[it])
            dfs(it);
}

int main()
{
    //f.close();
    f>>N>>M;
    for(;M;M--){
        f>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    viz.reset();
    int rez=0;
    for(int i=1;i<=N;i++)
        if(!viz[i]){
            rez++;
            dfs(i);
        }
    g<<rez;
    return 0;
}