#include <bits/stdc++.h>
#define NMAX 100000

using namespace std;

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

int n, m, a, b;
int nr_comp;
vector<int> graf[NMAX + 2];
bool viz[NMAX + 2];

void DFS(int nod) {
    viz[nod] = 1;
    for (int vec : graf[nod]) {
        if (!viz[vec]) {
            DFS(vec);
        }
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    fin.tie(NULL);
    fout.tie(NULL);

    fin >> n >> m;
    while (m--) {
        fin >> a >> b;
        graf[a].emplace_back(b);
        graf[b].emplace_back(a);
    }

    for (int i = 1; i <= n; i++) {
        if (!viz[i]) {
            nr_comp++;
            DFS(i);
        }
    }
    fout << nr_comp++;
    return 0;
}