#include <bits/stdc++.h>

using namespace std;

bool viz[100000];
vector <int> G[100000];

void DFS(int x)
{
    viz[x]=1;
    for (unsigned i=0; i<G[x].size(); i++)
    {
        if (!viz[G[x][i]]) DFS(G[x][i]);
    }
}

int main()
{
    ifstream f("dfs.in");
    ofstream g("dfs.out");
    int N,M,nrcomp=0;
    f>>N>>M;
    for (int i=0; i<M; i++)
    {
        int x,y;
        f>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for (int i=1; i<=N; i++)
    {
        if (!viz[i])
        {
            nrcomp++;
            DFS(i);
        }
    }
    g<<nrcomp;
    return 0;
}