#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
std::ifstream fin("dfs.in");
std::ofstream fout("dfs.out");
const int NMAX = 100005;
std::vector<int> G[NMAX + 1];
int vis[NMAX + 1];
int d[NMAX + 1];
int cc; //pentru nr de comp conexe

void DFS(int x)
{
    //fout << x << " ";
    vis[x] = 1;
    for(auto next : G[x])
        if(!vis[next])
        {
            DFS(next);
        }
}

int main()
{
    int n, m;
    int s;
    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(!vis[i])
        {
            cc++;
            DFS(i);
        }
    fout << cc;
    return 0;
}