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

const int NMAX=100000;
vector <int> G[NMAX+5];
bool viz[NMAX+5];
void dfs(int u)
{
    viz[u]=1;
    for(int i=0;i<(int)G[u].size();i++)
    {
        int v=G[u][i];
        if(!viz[v])
        dfs(v);
    }
}
int main()
{
    int n,m,u,v,s,componente=0;
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    scanf ("%d%d", &n, &m);
    for(int i=1;i<=m;i++)
    {
        scanf("%d%d", &u, &v);
        G[u].push_back(v);
        G[v].push_back(u);
    }
    for(int i=1;i<=n;i++)
    {
        if(viz[i]==0)
        {
            ++componente;
            dfs(i);
        }
    }
 printf("%d\n", componente);
 return 0;
}