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

using namespace std;

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

void DFS(int vertex,vector<vector<int>> v,bool visit[])
{
    visit[vertex]=1;
    for(int i=0;i<v[vertex].size();i++)
    {
        if(!visit[v[vertex][i]])
        {
            DFS(v[vertex][i],v,visit);
        }
    }
}


int main()
{
    int n,m,a,b;
    fin>>n>>m;
    vector<vector<int>>v(n+1);
    while(m)
    {
        fin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
        m--;
    }

    bool *visit=(bool*)calloc(n+1, sizeof(bool));
    int nrcmp=0;
    
    
    for(int i=1;i<=n;i++)
    {
        if(!visit[i]) //unvisited
        {
            nrcmp++;
            DFS(i,v,visit);
        }
    }
    fout<<nrcmp;
    
  
    return 0;
}