#include <bits/stdc++.h>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");

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() {
    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;
    return 0;
}