/*
    Keep It Simple!
*/

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

#define MaxN 100005

int N,M,C;
bool viz[MaxN];
vector<int> G[MaxN];

void DFS(int node)
{
    viz[node]=1;
    for(size_t i=0;i<=G[node].size();i++)
        if(!viz[G[node][i]])
            DFS(G[node][i]);
}

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

    f >> N >> M;

    int x,y;

    for(int i=1;i<=M;i++)
        {
            f >> x >> y;
            G[x].push_back(y);
            G[y].push_back(x);
        }

    for(int i=1;i<=N;i++)
        if(!viz[i])
        {
            C++;
            DFS(i);
        }

    g << C;
}