#include <fstream>
#include <vector>

using namespace std;

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

const int DMAX = 100001;

int n, m;
int viz[DMAX];
vector<int> G[DMAX];

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

int main()
{
    f >> n >> m;
    for (int i = 1; i <= m; i++){
        int x, y;
        f >> x >> y;

        G[x].push_back(y);
        G[y].push_back(x);
    }

    int nrc = 0;
    for (int i = 1; i <= n; i++){
        if (!viz[i]){
            dfs(i);
            nrc++;
        }
    }

    g << nrc;

    return 0;
}