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

using namespace std;

string filename = "dfs";

ifstream fin(filename + ".in");
ofstream fout(filename + ".out");

const int NMAX = 1e5;

bool vis[NMAX + 5];
vector<int> adj[NMAX + 5];

void dfs(int nod)
{
    vis[nod] = true;
    for(auto it : adj[nod])
    {
        if(!vis[it])
            dfs(it);
    }
}

int main()
{
    int n,m;
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int x,y;
        fin>>x>>y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }
    int rez=0;
    for(int i=1;i<=n;i++)
    {
        if(!vis[i])
        {
            rez++;
            dfs(i);
        }
    }
    fout<<rez;
    return 0;
}