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

ifstream fin("dfs.in");
ofstream fout("dfs.out");

const int nmax = 1e5;
vector<int> L[nmax + 1];
int vis[nmax + 1];

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

int main() {
    int n,m;
    fin >> n >> m;
    for(int i=1; i<=m; i++) {
        int x, y;
        fin >> x >> y;
        L[x].push_back(y);
        L[y].push_back(x);
    }
    int cc = 0;
    for(int i=1; i<=n; i++) {
        if(vis[i] == 0) {
            cc++;
            dfs(i);
        }
    }

    fout << cc;
}