#include <iostream>
#include <vector>
#include <fstream>
#include <queue>

using namespace std;

ifstream in("dfs.in");
ofstream out("dfs.out");

void dfs(int nod,vector <vector<int>> Graf,vector <int> &dist)
{
    dist[nod]=1;
    for(auto i: Graf[nod])
    {
        if(dist[i]==0)
            dfs(i,Graf,dist);
    }
}
int main()
{
    int n,m;
    int inf=10000;
    in>>n>>m;
    vector <vector<int>> Graf(n+1);
    vector <int>dist(n+1,0);
    for(int i=0;i<m;i++)
    {
        int x,y;
        in>>x>>y;
        Graf[x].push_back(y);
        Graf[y].push_back(x);
    }
    int term=0;
    int nr_comp=0;
    for (int i = 1; i <= n; i++) {
		if (dist[i] == 0) {
			dfs(i,Graf, dist);
			nr_comp++;
		}
	}
    out<<nr_comp;
    return 0;
}