#include<fstream>
#include<vector>
#include<queue>
#define mx 100001
using namespace std;
ifstream fin("dfs.in");
ofstream gout("dfs.out");
vector<int> v[mx];
queue<int> q;
vector<bool> viz;
int n,m;
void citire()
{
    int i,x,y;
    fin>>n>>m;
    viz.resize(n+1);
    for(i=1;i<=m;i++)
    {
        fin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);

    }
    fin.close();
}
void dfs(int s)
{
    viz[s]=true;
    for(unsigned int i=0;i<v[s].size();++i)
        if(!viz[v[s][i]])
    dfs(v[s][i]);
}
int main()
{
    int i,nr=0;
    citire();
    for(i=1;i<=n;i++)
        if(!viz[i])
    {
        nr++;
        viz[i]=true;
        dfs(i);
    }
    gout<<nr<<" ";
    return 0;
}