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

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

int n, m;
int marked[100005];

std::vector<int> g[100005];

int dfs(int node){
//    std::cout << "Marked node " << node << '\n';
    marked[node]=1;
    for(int i = 0; i < g[node].size(); i++) {
        int new_node = g[node][i];
        if (!marked[new_node])
            dfs(new_node);
    }
}

int main() {
    in >> n >> m;
    for (int i = 1; i <= m; i++)
        {
            int a, b;
            in >> a >> b;
            g[a].push_back(b);
            g[b].push_back(a);
        }

    int cont = 0;

    for(int i = 1; i <= n; i++)
    {
        if(!marked[i])
        {
            dfs(i);
            cont++;
        }
    }
    out << cont;




    return 0;
}