#include <fstream>
#include <vector>

using namespace std;

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

void dfs (int a)
{
    int j;
    viz[a]=1;
    for (j=0; j<v[a].size(); j++)
    {
        if (viz[v[a][j]]==0)
        {
            dfs(v[a][j]);
        }
    }
}

int main()
{
    freopen ("dfs.in","r",stdin);
    freopen ("dfs.out","w",stdout);

    int m,n;
    scanf ("%d %d",&n,&m);

    int i,x,y;
    for (i=1; i<=m; i++)
    {
        scanf ("%d %d",&x,&y);
        v[x].push_back(y);
        v[y].push_back(x);
    }

    int nr=0;
    for (i=1; i<=n; i++)
    {
        if (viz[i]==0)
        {
            dfs(i);
            nr++;
        }
    }

    printf ("%d\n",nr);

    return 0;
}