#include <bits/stdc++.h>

using namespace std;

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

vector<int> G[100005];
int viz[100005];
int n,m;

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

int main() {
    int sol=0,a,b,i;
    fin>>n>>m;
    for(i = 1; i <= m; i++){
        fin>>a>>b;
        G[a].push_back(b);
        G[b].push_back(a);
    }
    for(i = 1; i <= n; i++){
        if(viz[i] == 0){
            sol++;
            dfs(i);
        }
    }
    fout<<sol<<'\n';
    return 0;
}