#include <fstream>
#include <vector>
using namespace std;
ifstream in("dfs.in");
ofstream out("dfs.out");
vector <int> G[100005];
int viz[100005],cnt;
void dfs (int nod)
{
    viz[nod]=cnt;
    int l=G[nod].size();
    for(int i=0; i<l; i++)
    {
        int x=G[nod][i];
        if(!viz[x])
        dfs(x);
    }
}
int main()
{
    int n,m,x,y;
    in>>n>>m;
    for(int i=1; i<=m; i++)
    {
        in>>x>>y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for(int i=1; i<=n; i++)
        if(viz[i]==0)
    {
        cnt++;
        dfs(i);
    }
    out<<cnt;
    return 0;
}