#include <iostream>
#include <fstream>
#include <vector>
#include <unordered_map>
#include <unordered_set>
#include <stack>

using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int NMAX = 1e5;

vector<int> L[NMAX - 1];
int viz[NMAX + 1];

void dfs(int node) 
{
    viz[node] = 1;
    for (int neighbor : L[node]) {
        if (!viz[neighbor]) {
            dfs(neighbor);
        }
    }
}

int main() 
{
    int n, m;
    fin >> n >> m;

    for (int i = 0; i < m; ++i) {
        int u, v;
        fin >> u >> v;
        L[u].push_back(v);
        L[v].push_back(u);
    }

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

    fout << connectedComponents << '\n';

    return 0;
}