#include <bits/stdc++.h>

using namespace std;

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

vector <vector <int>> v;
int nr = 0;
int viz[100010];

void DFS(int node) {
    viz[node] = 1;
    for(int i = 0; i < v[node].size(); i++) {
        if(viz[v[node][i]] == 0) {
            DFS(v[node][i]);
        }
    }
}

int main()
{
    int n, m;
    f >> n >> m;
    v.resize(n + 1);
    for(int i = 0 ; i < m; i++) {
        int x, y;
        f >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i = 1; i <= n; i++) {
        if(viz[i] == 0) {
            nr++;
            DFS(i);
        }
    }
    g << nr;
    return 0;
}