#include <fstream>
#include <bits/stdc++.h>

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int n, m, i, j, x, y, nrc;
bool viz[100005];
vector <int> v[100005];
void dfs(int nod)
{
    viz[nod]=1;
    for(auto i: v[nod])
        if(viz[i]==0)
            dfs(i);
}
int main()
{
    fin>>n>>m;
    for(i=1; i<=m; i++)
    {
        fin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(i=1; i<=n; i++)
        if(viz[i]==0)
    {
        nrc++;
        dfs(i);
    }
    fout<<nrc;
    return 0;
}