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

using namespace std;

const string filename = "dfs";
ifstream fin(filename + ".in");
ofstream fout(filename + ".out");

int n, m, cc;
bool used[100005];
vector <int> G[100005];

void dfs(int nod)
{
    used[nod] = 1;
    for(int vecin : G[nod])
        if(!used[vecin])
            dfs(vecin);
}

int main()
{
    fin >> n >> m;
    for(int i = 1; i <= m; i++)
    {
        int x, y;
        fin >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }
    for(int i = 1; i <= n; i++)
        if(!used[i])
            cc++, dfs(i);
    fout << cc;
    return 0;
}