#include <bits/stdc++.h>

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");

vector<int>v[100005];
int n,m,u,y,viz[100005],nrcomp;

void dfs(int x)
{
    viz[x]=nrcomp;

    for(auto i:v[x])
    {
        if(viz[i]==0)
            dfs(i);
    }
}

int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++)
    {
        fin>>u>>y;
        v[u].push_back(y);
        v[y].push_back(u);
    }
    for(int i=1; i<=n; i++)
    {
        if(viz[i]==0)
        {
            nrcomp++;
            dfs(i);
        }
    }
    fout<<nrcomp;
}