#include <bits/stdc++.h>
#define ll long long
#define MOD 1000000007

using namespace std;
string fis="dfs";
ifstream fin(fis+".in");
ofstream fout(fis+".out");
const int nMax=1e5;
int n,m,x;
vector<int>Edges[nMax];
bool beenThere[nMax];

void dfs(int nod)
{
    beenThere[nod]=1;

    for(int i=0;i<Edges[nod].size();i++)
    {
        int nh=Edges[nod][i];
        if(!beenThere[nh])
        {
            dfs(nh);
        }
    }
}

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

    int cnt=0;
    for(int i=1;i<=n;++i)
    {
        if(!beenThere[i])
        {
            ++cnt;
           // sort(Edges[i].begin(),Edges[i].end());

            dfs(i);
        }
    }

    fout<<cnt;
}