// Source: https://usaco.guide/general/io

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

vector<int> L[100001];
int vis[100001];

void dfs(int node) {
    vis[node] =1;
    for (auto vec : L[node]) {
        if (vis[vec] == 0) {
            dfs(vec);
        }
    }
}

int main() {
    ifstream in("dfs.in");
    ofstream out("dfs.out");
    int n, m;
    in >> n >> m;
    for (int i = 1; i <= m; i++) {
        int a,b ;
        in >> a >> b;
        L[a].push_back(b);
        L[b].push_back(a);
    }
    int nr = 0;
    for (int i = 1; i <= n; i++) { 
        if (vis[i] == 0) { 
            nr++;
            dfs(i);
        }
    }

    out << nr;
}