#include <bits/stdc++.h>
#define DIM 100001
using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

int n, m, a, b, conex;
bool parcurs[DIM];
vector <int> G[DIM];

void dfs(int nod){
    parcurs[nod]=1;
    for(int i=0; i<G[nod].size(); i++){
        if(!parcurs[G[nod][i]])
            dfs(G[nod][i]);
    }
}

int main(){
    fin>>n>>m;
    for(int i=1; i<=m; i++){
        fin>>a>>b;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    for(int i=1; i<=n; i++){
        if(!parcurs[i]){

            dfs(i);
            conex++;
        }
    }
    fout<<conex;
}