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

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

bitset <100001> viz;
vector <vector <int>> a;
int n, m, x, y, i, pc;

void dfs(int v){
    viz[v]=1;
    for(int i:a[v]){
        if(!viz[i]) dfs(i);
    }
}

int main(){
    fin>>n>>m;
    a.assign(n+1, vector <int>());
    for(i=1;i<=m;i++){
        fin>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }

    for(i=1;i<=n;i++){
        if(!viz[i]){
            dfs(i);
            pc++;
        }
    }
    fout<<pc;
    return 0;
}