#include <iostream>
#include <vector>
#include <fstream>
using namespace std;

ifstream f("dfs.in");
ofstream o("dfs.out");
const int nmax = 100000;
vector<int> G[nmax+1];
int vis[nmax+1];
void DFS(int x){
    vis[x]=1;
    for(int i=0; i<G[x].size(); i++)
    {
        if(!vis[G[x][i]])DFS(G[x][i]);
    }

}

/*int d[nmax+1];
void BFS(int x){
    queue<int> q;
    q.push(x);
    d[x]=0;
    vis[x] = 1;
    while(!q.empty()){
        x = q.front();
        cout<<x<<" ";
        q.pop();
        for(auto next:G[x]){
            if(!vis[next]){
                q.push(next);
                vis[next] = 1;
                d[next] = d[x] + 1;
            }
        }
    }
}*/
int main()
{
    int n,m;
    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);
    }
    int cc =  0;
    for(int i = 1; i<=n; i++){
        if(!vis[i]){
            cc++;
            DFS(i);
        }
    }
    o<<cc;
    return 0;
}