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

using namespace std;

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

const int NRMAX=100001;
vector<int> G[NRMAX];
int viz[NRMAX],n,m;

void dfs(int x)
{
    viz[x]=1;
    for(int num:G[x])
    {
        if(!viz[num])
        {
            dfs(num);
        }
    }
}

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