#include <fstream>
#include <queue>
#include <vector>
#include <bitset>

using namespace std;

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

const int N = 1e5;

vector <int> a[N+1];
bitset <N+1> viz;
void dfs(int x)
{
    viz[x] = 1;
    for(auto y:a[x])
    {
        if(!viz[y])
        {
            dfs(y);
        }
    }
}

int main()
{
    int n, m;
    cin >> n >> m;
    for(int i = 0; i < m; i++)
    {
        int x, y;
        cin >> x >> y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    int nrc = 0;
    for(int i = 1; i <= n; i++)
    {
        if(!viz[i])
        {
            nrc++;
            dfs(i);
        }
    }
    cout << nrc;
    return 0;
}