#include <bits/stdc++.h>

#define NMAX 100005

using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

int N, M, i, x, y, nrcmp, viz[NMAX];
vector <int> G[NMAX];

void dfs(int nod)
{
    viz[nod] = 1;
    int nrvecini = G[nod].size();
    for (int i=0; i<nrvecini; i++)
    {
        int vecin = G[nod][i];
        if (viz[vecin] == 0)
            dfs(vecin);
    }
}

int main()
{
    fin >> N >> M;

    for (i=0; i<M; i++)
    {
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }

    for (i=1; i<=N; i++)
    {
        if (viz[i] == 0)
        {
            nrcmp++;
            dfs(i);
        }
    }

    fout << nrcmp;

    return 0;
}