#include <fstream>
#include <vector>
using namespace std;

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

int n, m;
vector <int> Edge[100005];

bool viz[100005];
int rasp;

void DFS(int Node) {
    viz[Node] = true;
    for (int i = 0; i < Edge[Node].size(); ++i) {
        int Next = Edge[Node][i];
        if(!viz[Next])
            DFS(Next);
    }
}

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

int main() {
    citire();
    for(int i = 1; i <= n; ++i) {
        if (!viz[i]) {
            ++rasp;
            DFS(i);
        }
    }

    cout << rasp;
    return 0;
}