#include <fstream>
#include <vector>
using namespace std;

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

#define MAX 100005

int n, m, a, b;
bool viz[MAX];
vector<int> g[MAX];

void dfs(int nod)
{
    for(int i = 0; i < g[nod].size(); ++i)
    {
        if(!viz[g[nod][i]])
        {
            viz[g[nod][i]] = true;
            dfs(g[nod][i]);
        }
    }
}

int main()
{
    cin >> n >> m;
    for(int i = 1; i <= m; ++i)
    {
        cin >> a >> b;
        g[a].push_back(b);
        g[b].push_back(a);
    }
    int k = 0;
    for(int i = 1; i <= n; ++i)
    {
        if(!viz[i])
        {
            k++;
            dfs(i);
        }
    }
    cout << k << '\n';
}