#include <fstream>
#include <vector>
using namespace std;
const int nr = 1e5;
vector<int> G[nr+1];
int vis[nr+1];

void DFS(int x){
    vis[x] = 1;
    for(auto next:G[x])
        if(!vis[next])
            DFS(next);
}

int main() {
    int n, m, s;
    ifstream f;
    ofstream g;
    f.open("dfs.in");
    f>>n>>m;
    for(int i = 1; i <= m; i++){
        int x,y;
        f>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    f.close();
    int contor = 0;
    for(int i = 1; i <= n; i++){
        if(!vis[i]){
            contor++;
            DFS(i);
        }
    }
    g.open("dfs.out");
    g<<contor;
    g.close();
    return 0;
}