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

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

const int NMAX = 100001;
int n, m;
bool vis[NMAX];
vector <int> Ad[NMAX];
queue < int > Q;

void DFS (int nod)
{
    vis[nod] = 1;
    int w;
    for (int i = 0; i < Ad[nod].size(); i++)
    {
        w = Ad[nod][i];
        if (vis[w] == 0)
        {
            DFS(w);
        }
    }
}

int main()
{
    fin >> n >> m;
    int x,y;
    for (int i = 1; i <= m; i++)
    {
        fin >> x >> y;
        Ad[x].push_back(y);
        Ad[y].push_back(x);
    }
    int cnt = 0;
    for (int i = 1; i <= n; i++)
    {
        if (vis[i] == 0)
        {
            cnt++;
            DFS(i);
        }
    }
    fout << cnt; 
    return 0;
}