#include <iostream>
#include <fstream>
#include <vector>
#include <queue>

using namespace std;

int n, m;

ifstream f("dfs.in"); ofstream g("dfs.out");

vector <int> vecini[100005];

int viz[100005];

int comp;

void DFS(int nod, int comp){
    int i;
    viz[nod] = comp;
    for(i = 0; i < vecini[nod].size(); ++i) {
        if(!viz[vecini[nod][i]]) {
            DFS(vecini[nod][i],comp);
        }
    }
}

int main() {
    int i,x,y;
    f>>n>>m;
    for(i = 1; i <= m; ++i) {
        f>>x>>y;
        vecini[x].push_back(y);
        vecini[y].push_back(x);
    }
    comp = 0;
    for(i = 1; i <= n; ++i) {
        if(!viz[i]) {
            ++comp;
            DFS(i,comp);
        }
    }
    g<<comp;
    return 0;
}