#include <fstream>
#include <vector>

using namespace std;

vector <int> v[100001];

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

int n, m;

bool viz[100001];

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

}

int main()
{
    cin >> n >> m;
    for(int i = 1; i<=m; i++)
    {
        int x, y;
        cin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    int nr = 0;
    for(int i = 1; i<=n; i++)
    {
        if(viz[i] == 0)
        {
            nr++;
            dfs(i);
        }
    }
    cout << nr;

    return 0;
}