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

using namespace std;

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

int n, m;
vector <int> G[100001];
int viz[100001];

void dfs(int node)
{
    viz[node] = 1;
    for(auto it:G[node])
        if(!viz[it])
            dfs(it);
}

int main()
{
    int x, y;
    fin>>n>>m;
    for(int i=0; i<m; i++)
    {
        fin>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for(int i=1; i<=n; i++)
        viz[i] = 0;

    int nrComp = 0;
    for(int i=1; i<=n; i++)
        if(!viz[i])
        {
            nrComp++;
            dfs(i);
        }
    fout<<nrComp;
    return 0;
}