#include <iostream>
#include <vector>
#include <fstream>

using namespace std;

vector<int> v[100005];

int viz[100001];

void dfs(int nod){
    viz[nod] = 1;

    for(int i = 0; i < v[nod].size(); ++i){
        if(viz[ v[nod][i] ] == 0)
            dfs(i);
    }
}


int main()
{
    ifstream in("dfs.in	");

    int n, m;
    in >> n >> m;

    for(int i = 0; i < m; ++i){
        int x, y;
        in >> x >> y;

        v[x].push_back(y);
        v[y].push_back(x);
    }

    ofstream out("dfs.out");

    int nrc(0);

    for(int i = 0; i < n; ++i){
        if(viz[i] == 0)
        {
            nrc++;
            dfs(i);
        }
    }
    out << nrc << endl;

    return 0;
}