#include<fstream>
#include<vector>
using namespace std;

ifstream cin("dfs.in");
ofstream cout("dfs.out");

vector<int> v[100001];
int viz[100001];

void dfs(int a)
{
    viz[a] = true;
    int ct = v[a].size();
    for(int i=0; i<ct; i++)
    {
        int vecin = v[a][i];
        if(viz[vecin] == 0)
            dfs(vecin);
    }
}

int main()
{
    int n, m;
    cin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        int x, y;
        cin>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    int rez = 0;
    for(int i=1; i<=n; i++)
    {
        if(viz[i] == 0)
        {
            rez++;
            dfs(i);
        }
    }
    cout<<rez;
    return 0;
}