#include <bits/stdc++.h>


using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector<int> L[100005];
bool viz[100005];
void DFS(int nod)
{
    //cout<<nod<<" ";
    viz[nod]=1;
    for(int j=0;j<L[nod].size();j++)
        if(viz[L[nod][j]]==0)
            DFS(L[nod][j]);
}
int main()
{
    int n,m;
    fin>>n>>m;
    for(int i=1;i<=m;i++)
    {
        int x,y;
        fin>>x>>y;
        //cout<<x<<" "<<y<<"\n";
        L[x].push_back(y);
        L[y].push_back(x);
    }
    
    int cc=0;
    for(int i=1;i<=n;i++)
        if(viz[i]==0)
        {
            DFS(i);
            cc++;
        }
    fout<<cc;
    return 0;
}