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

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

int viz[100003];
vector <int> graph[100003];

void DFS(int nod)
{
    viz[nod]= 1;
    int lim= graph[nod].size();
    for(int i= 0; i< lim; i++)
    {
        int vecin= graph[nod][i];
        if(!viz[vecin])
            DFS(vecin);
    }

}

int main()
{
    int n, answer=0, a, b, m;
    f>>n;
    f>>m;

        for (int i=0; i< m; i++)
    {
        f>>a>>b;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }

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

    g<<answer;

    return 0;
}