#include <bits/stdc++.h>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
vector<int>v[100010];
int n,m,i,a,b,viz[100010],cnt;
void dfs(int nod)
{
    viz[nod]=1;
    for(auto urmator:v[nod])
        if(viz[urmator]==0)
            dfs(urmator);
}
int main()
{
    fin>>n>>m;
    for(i=1;i<=m;i++)
    {
        fin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    for(i=1;i<=n;i++)
        if(viz[i]==0)
        {
            cnt++;
            dfs(i);
        }
    fout<<cnt;
}