#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <bitset>

#define dim 100009
#define pb push_back
using namespace std;
ofstream out("dfs.out");

int n;
bitset <dim> uz;

vector < int >G[dim];

void read();
void dfs(int nod);

int main()
{
    read();
    int nrComp = 0;
    for(int i = 1 ; i<=n; ++i)
        if(!uz[i])
    {
        ++nrComp;
        dfs(i);
    }

    out << nrComp << '\n';
    return 0;
}

void read()
{
    ifstream in("dfs.in");
    int m;
    in >> n >> m;
    for(int x,y; m; --m)
    {
        in >> x >> y;
        G[x].pb(y);
        G[y].pb(x);
    }

}

void dfs(int root)
{
    uz[root] = 1;
    for(vector <int>:: iterator I = G[root].begin(); I!= G[root].end(); ++I)
        if(!uz[*I])
        {
            dfs(*I);
        }
}