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

ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int MAX_NODES_COUNT = 100013;

vector<int> adjList[MAX_NODES_COUNT];
int n, m, x, y;
bool visited[MAX_NODES_COUNT];

void dfs(int node)
{
    visited[node] = true;
    for (int rNode : adjList[node])
    {
        if (!visited[rNode])
        {
            dfs(rNode);
        }
    }
}

int main()
{
    fin >> n >> m;
    while (m--)
    {
        fin >> x >> y;
        adjList[x].push_back(y);
        adjList[y].push_back(x);
    }
    int cnt = 0;
    for (int i = 1; i <= n; ++i)
    {
        if (!visited[i])
        {
            ++cnt;
            dfs(i);
        }
    }
    fout << cnt;
    fout.flush();
}