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

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

const int N= 1e5+5;

int n;
vector<int> la[N];
bool parcurs[N];

void dfs(int nod)
{
    if(parcurs[nod]) return;
    parcurs[nod]=1;

    for(int i=0;i<la[nod].size();i++)
        dfs(la[nod][i]);
}

int main()
{
    int m; in>>n>>m;

    for(int i=1; i<=m; i++)
    {
        int x,y; in>>x>>y;
        la[x].push_back(y);
        la[y].push_back(x);
    }


    int nrCC=0;
    for(int i=1; i<=n; i++)
        if(!parcurs[i])
        {
            nrCC++;
            dfs(i);
        }

    out<<nrCC;
}