#include <fstream>
#include <vector>

using namespace std;

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

const int N = 1e5;
vector < vector <int> > graph;
bool viz[N + 1];

void dfs(int nod){
    viz[nod] = 1;
    for(int vec : graph[nod]){
        if(!viz[vec])
            dfs(vec);
    }
}

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