#include <bits/stdc++.h>
using namespace std;

const int NMAX = 1e5;
vector<int> L[NMAX + 1];
int vis[NMAX + 1];
//vector<vector<int>> L2;

void dfs(int node) {//O(n + m)
    //cout << node <<  ' ';
    vis[node] = 1;
    for(auto vec : L[node]) {
        if(!vis[vec]) {
            dfs(vec);
        }
    }
}

int main() {
    ifstream cin("dfs.in");
    ofstream cout("dfs.out");
	int n, m;
    cin >> n >> m;
    //L2.resize(n + 1, vector<int>());
    for(int i = 1; i <= m; i++) {
        int x, y;
        cin >> x >> y;
        L[x].push_back(y);
        L[y].push_back(x); //daca graful este orientat linia asta dispare
    }
    //dfs(1);
    int cc = 0;
    for(int i = 1; i <= n; i++) {
        if(vis[i] == 0) {
            cc++;
            dfs(i);
        }
    }
    cout << cc;
}