#include <fstream>
#include <algorithm>
#include <vector>
using namespace std;

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

const int MAX_N = 100100;

vector<int> A[MAX_N];

bool viz[MAX_N];

void dfs(int nod) {
    viz[nod] = true;
    for(auto it : A[nod]) {
        if(!viz[it]) {
            dfs(it);
        }
    }
}

int main() {
    int n, m;
    fin >> n >> m;
    for(int i = 1; i <= m; i++) {
        int a, b;
        fin >> a >> b;
        A[a].push_back(b);
        A[b].push_back(a);
    }
    
    int comp = 0;
    
    for(int i = 1; i <= n; i++) {
        if(!viz[i]) {
            dfs(i);
            ++comp;
        }        
    }
    
    fout << comp << '\n';
}