#include <iostream>
#include <fstream>
#include <vector>
#define DIM 100002

using namespace std;

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

int n, m, x, y, sol;

bool viz[DIM];

vector<int> graf[DIM];

void dfs(int nod){
    viz[nod] = true;
    for(int i = 0; i < graf[nod].size(); ++ i){
        int nodc = graf[nod][i];
        if(!viz[nodc])
            dfs(nodc);
    }
}

int main(int argc, const char * argv[]) {
    in>>n>>m;
    for(int i = 1; i <= m; ++ i){
        in>>x>>y;
        graf[x].push_back(y);
        graf[y].push_back(x);
    }
    for(int i = 1; i <= n; ++ i){
        if(!viz[i]){
            dfs(i);
            ++ sol;
        }
    }
    out<<sol;
    return 0;
}