#include <fstream>
#include <vector>

using namespace std;
ifstream in("dfs.in");
ofstream out("dfs.out");

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

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

int main()
{
    int n, m, i, x, y;
    in >> n >> m;
    for(i=1; i<=m; i++)
    {
        in >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    /////////////////////

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