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

using namespace std;

string problema = "dfs";

ifstream in(problema+".in");
ofstream out(problema+".out");

int n,m,cnt;

vector<int> nod[100001];
bool visited[100001];

void dfs(int n)
{
    for(int pNod : nod[n])
    {
        if(!visited[pNod])
        {
            visited[pNod]=1;
            dfs(n);
        }
    }
}

int main()
{
	in>>n>>m;
	for(int i = 1; i <= m; i++)
    {
        int x,y;
        in>>x>>y;
        nod[x].push_back(y);
        nod[y].push_back(x);
    }
    for(int i = 1;i<=n;i++)
    {
        if(!visited[i]){
            visited[i]=1;
            cnt++;
            dfs(i);
        }
    }
    out<<cnt;
    return 0;
}