#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

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

int n, m, x, y;
int comps;

bool viz[100005];

vector <int> G[100005];

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

    for(auto v : G[nod])
    {
         if(!viz[v])
            dfs(v);
    }
}

int main()
{
    in >> n >> m;
    for(int i = 1; i <= m; ++ i)
    {
        in >> x >> y;

        G[x].push_back(y);
        G[y].push_back(x);
    }

    for(int i = 1; i <= n; ++ i)
        if(!viz[i])
        {
            ++ comps;
            dfs(i);
        }

    out << comps;
    return 0;
}