#include <fstream>
#include <vector>

using namespace std;

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

const int MAX = 1e5 + 1;
vector<int> adj[MAX];
int n, m, viz[MAX];

void dfs(int nod)
{
    viz[nod] = 1;

    for(unsigned i = 0; i < adj[nod].size(); ++i)
    {
        int fiu = adj[nod][i];

        if(viz[fiu] == 0)
        {
            dfs(fiu);
        }
    }
}

int main()
{
    cin >> n >> m;

    for(int i = 1; i <= m; ++i)
    {
        int x, y;
        cin >> x >> y;
        adj[x].push_back(y);
        adj[y].push_back(x);
    }

    int ans = 0;

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

    cout << ans;

    return 0;
}