#include <iostream>
#include <fstream>
#include <cstdio>
#include <cstring>
#include <vector>
#include <queue>
#define NMax 100001
using namespace std;

ifstream f("dfs.in");
ofstream g("dfs.out");

int n, m, x, y, comp;
vector<int> G[NMax];
bool viz[NMax];

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

}

int main()
{
    f >> n >> m;
    for(int i = 1; i <= m; ++i)
    {
        f >> x >> y;
        G[x].push_back(y);
        G[y].push_back(x);
    }

    for(int i = 1; i <= n; ++i)
        if(!viz[i])
        {
            ++comp;
            dfs(i);
        }

    g << comp << '\n';
    return 0;
}