#include <iostream>
#include <vector>
#include <queue>
#include <stdio.h>

#define Nmax 100005

using namespace std;

vector<int> G[Nmax];

int n,m, nr;
int viz[Nmax];

void citire()
{
    int x, y;
    scanf("%d %d\n", &n, &m);
    for(int i=1; i<=m; ++i)
    {
        scanf("%d %d\n", &x, &y);
        G[x].push_back(y);
        G[y].push_back(x);
    }
}

void parcurgere(int vf)
{
    viz[vf] = 1;
    for(vector<int>::iterator it = G[vf].begin(); it != G[vf].end(); ++it)
        if(!viz[*it])
            parcurgere(*it);
}

int numarare()
{
    for(int i =1; i<=n; ++i)
        if(!viz[i])
        {
            parcurgere(i);
            ++nr;
        }
    return nr;
}

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

    citire();
    printf("%d ", numarare());

    return 0;
}