#include <fstream>
#include <vector>
using namespace std;
ifstream cin ("dfs.in");
ofstream cout("dfs.out");
vector<int> L[100010];
vector<int> C[100010];
int viz[100010];
int n, m, i, x, y, cc, j;
void dfs(int nod) {
    viz[nod] = cc;
    C[cc].push_back(nod);
    for (int i = 0; i<L[nod].size(); i++) {
        int vecin = L[nod][i];
        if (viz[vecin] == 0)
            dfs(vecin);
    }
}
int main () {
    cin>>n>>m;
    for (i=1;i<=m;i++) {
        cin>>x>>y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    for (i=1;i<=n;i++)
        if (viz[i] == 0){
            cc++;
            dfs(i);
        }
    cout<<cc<<"\n";
}