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

void dfs(vector<vector<int>> &graph, vector<bool> &isVisited, int node) {
    isVisited[node] = 1;

    for(int neighbour : graph[node]) {
        if(!isVisited[neighbour]) {
            dfs(graph, isVisited, neighbour);
        }
    }
}

int main() {
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");
    int n,m;
    fin >> n >> m;
    vector<vector<int>> graph(n+1, vector<int>());

    for(int i=1; i<=m; i++) {
        int x,y;
        fin >> x >> y;
        graph[x].push_back(y);
        graph[y].push_back(x);
    }
    int sol = 0;
    vector<bool> isVisited(n+1);

    for(int i=1; i<=n; i++) {
        if(!isVisited[i]) {
            sol++;
            dfs(graph, isVisited, i);
        }
    }

    fout << sol;
    
    return 0;
}