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


const int NMAX = 100000;


vector<int> v[NMAX+5];


int  viz[NMAX + 5];

int cc;

void DFS(int sursa)
{
    int i;
    viz[sursa]=1;
    for(i=0; i<v[sursa].size(); ++i)
    {
        if(!viz[v[sursa][i]])
            DFS(v[sursa][i]);
    }
}

int main()
{

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

    int n,m;
    int i,j;
    int a,b;


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

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

    for(i=1; i<=n; ++i)
        if(!viz[i])
        {
            DFS(i);
            ++cc;
        }

    printf("%d",cc);

}