#include <fstream>
#include <vector>

using namespace std;

ifstream cin("dfs.in");
ofstream cout("dfs.out");

int n, m;
vector <int> vecini[100001];
bool viz[100001];


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

int main()
{
    int x, y, k = 0;
    cin >> n >> m;
    for(int i = 1; i <= m; i++)
    {
        cin >> x >> y;
        vecini[x].push_back(y);
        vecini[y].push_back(x);
    }

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

    cout << k;
}