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

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

ifstream f("dfs.in");
ofstream g("dfs.out");

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


int main() {
    int n,m;
    f>> n >>m;
    for (int i=1; i<=m; i++) {
        int a,b;
        f>>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);
        }
    }

    g<<nr;
}