#include <bits/stdc++.h>
using namespace std;
string np = "dfs";
ifstream f(np + ".in");
ofstream g(np + ".out");

// #define f cin
// #define g cout

int n, m;
bool viz[100003];
vector<int> adj[100003];

void dfs(int nod)
{
    viz[nod] = 1;
    for (auto u : adj[nod])
        if (!viz[u])
            dfs(u);
}
int main()
{
    ios_base::sync_with_stdio(false);
    f.tie(nullptr);

    f >> n >> m;
    for (int a, b; f >> a >> b;)
        adj[a].push_back(b), adj[b].push_back(a);

    int rez = 0;
    for (int i = 1; i <= n; i++)
        if (!viz[i])
            dfs(i), rez++;

    g << rez;

    return 0;
}