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

using namespace std;

vector<int>graph[100005];

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

int drumuri, noduri,x,y,viz[100005],nr;

void recurs(int x)
{
    viz[x]=1;
    for (auto &v:graph[x])
    {
        if (viz[v]==0)
            recurs(v);
    }
}

int main()
{
    f >> noduri >> drumuri;
    for (int i=0; i<drumuri; i++)
    {
        f>> x >> y;
        graph[x].push_back(y);
        graph[y].push_back(x);
    }
    for (int i=1; i<=noduri; i++)
    {
        if (viz[i]==0)
        {
            nr++;
            recurs(i);
        }
    }
    g << nr;
    return 0;
}