#include <fstream>
#include <vector>

#define NMAX 100007

using namespace std;

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

vector < int > v[NMAX];
int Viz[NMAX];
int n, m, Ans;

void dfs(int Node){
    Viz[Node] = 1;
    for(vector < int > :: iterator it = v[Node].begin(); it != v[Node].end(); ++it)
        if(Viz[*it] == 0)
            dfs(*it);
}

int main(){
    cin >> n >> m;
    for(int i = 1; i <= m; ++i){
        int a, b;
        cin >> a >> b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    for(int i = 1; i <= n; ++i)
        if(Viz[i] == 0){
            dfs(i);
            ++Ans;
        }
    cout << Ans;
    return 0;
}