#include <iostream>
#include <fstream>
#include <vector>
using namespace std;

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

vector <int> muchii[100001];
bool visited[100001];
int n, m;

void DFS(int nod)
{
    visited[nod]=1;
    for (auto next : muchii[nod])
        if (!visited[next])
            DFS(next);
}

int main()
{
    f>>n>>m;
    for (int i=1;i<=m;i++)
    { int x, y;
      f>>x>>y;
      muchii[x].push_back(y);
      muchii[y].push_back(x);
    }
    ///Problema infoarena DFS
    int cc=0;
    for (int i=1;i<=n;i++)
    { if (!visited[i])
      { cc++;
        DFS(i);
      }
    }
    g<<cc;
    return 0;
}