#include <fstream>
#include <vector>

using namespace std;

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

const int MAXN = 100000;

vector<int> L[MAXN + 1];
bool viz[MAXN + 1];

void dfs(int node){
    viz[node] = true;
    for(auto vec :L[node]){
        if(!viz[vec])
            dfs(vec);
    }
}

int main(){
    int n, m;
    fin >> n >> m;
    for(int i = 1; i <= m; i++){
        int a, b;
        fin >> a >> b;
        L[a].push_back(b);
        L[b].push_back(a);
    }
    int nr = 0;
    for (int i = 1; i <= n; i++) {
        if (!viz[i]) {
            nr++;
            dfs(i);
        }
    }
    fout << nr << "\n";

    fin.close();
    fout.close();

    return 0;
}