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

using namespace std;

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

int n,m,s,x,y;
vector  <int> gr[100010];
queue <int > q;
int viz[100005];

void bfs(int j)
{
    viz[j]=1;
    for (auto i:gr[j])
        {   if(viz[i]==0)
            bfs(i);
        }
}

void citire()
{
    f>>n>>m;
    for (int i=1; i<=m; i++)
    {
        f >> x>> y;
        gr[x].push_back(y);
        gr[y].push_back(x);
    }
}

int main()
{
    citire();
    int nr=0;
    for(int i=1;i<=n;i++)
    {
        if(viz[i]==0)
        {
            bfs(i);
            nr++;
        }
    }
    g<<nr;
    return 0;
}