#include<bits/stdc++.h>
#define maxn 1000
using namespace std;

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

int n,m,viz[maxn]={0};
int nr_componente=0;
queue <int> q;
vector <int> G[maxn];

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

void dfs(int x)
{
    int nod;

    q.push(x);
    viz[x]=1;

    while(!q.empty())
    {
        nod=q.front();
        q.pop();
        for(int i=0;i<G[nod].size();i++)
        {
            if(viz[G[nod][i]]==0)
            {
                viz[G[nod][i]]=1;
                q.push(i);
            }
        }
    }
}

int main()
{
    citire();
    for(int i=1;i<=n;i++)
    {
        if(viz[i]==0)
        {
            nr_componente++;
            dfs(i);
        }
    }
    fout<<nr_componente;
    return 0;
}