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

using namespace std;

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

int n,m,k;
int viz[100005];
vector < int > vecini[100005];

void dfs(int nod) {
    int i,nr;
    viz[nod] = k;
    nr = vecini[nod].size();
    for(i = 0; i < nr; ++i) {
        if(viz[vecini[nod][i]] == 0) {
            dfs(vecini[nod][i]);
        }
    }
    return;
}

int main() {
    int i,x,y;
    f>>n>>m;
    for(i = 1; i <= m; ++i) {
        f>>x>>y;
        vecini[x].push_back(y);
        vecini[y].push_back(x);
    }
    k = 0;
    for(i = 1; i <= n; ++i) {
        if(viz[i] == 0) {
            ++k;
            dfs(i);
        }
    }
    g<<k;
    return 0;
}