#include <iostream>
#include <fstream>
#include <vector>
#include <bitset>
#define MAX 100003

using namespace std;

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

vector<int> vec[MAX];
bitset<MAX> viz;

void dfs(int nod) {
    viz[nod] = 1;
    for(vector<int>::iterator it = vec[nod].begin(); it != vec[nod].end(); it++) {
        if(!viz[*it]) {
            dfs(*it);
        }
    }
}

int main() {

    int n,m,x,y;
    in >> n >> m;

    for(int i = 1; i <= m; i++) {
        in >> x >> y;
        vec[x].push_back(y);
        vec[y].push_back(x);
    }
    int comp = 0;
    for(int i = 1; i <= n; i++) {
        if(!viz[i]) {
            comp++;
            dfs(i);
        }
    }
    out << comp;

    return 0;
}