#include <fstream>
#include <vector>

using namespace std;

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

int n, m;
vector<int> G[100005]; 
bool viz[100005];

void dfs(int nod) {
    viz[nod] = true;
    
    for(int i = 0; i < G[nod].size(); i++) {
        int vecin = G[nod][i];
        if(!viz[vecin]) {
            dfs(vecin);
        }
    }
}

int main() {
    fin >> n >> m;
    
    int x, y;
    for(int i = 1; i <= m; i++) {
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    
    int componente_conexe = 0;
    
    for(int i = 1; i <= n; i++) {
        if(!viz[i]) {
            componente_conexe++;
            dfs(i);
        }
    }
    
    fout << componente_conexe;
    
    return 0;
}