#include <cstdio>
#include <algorithm>
#include <vector>

using namespace std;

const int NMAX=100000;

vector<int>G[NMAX+1];

int viz[NMAX+1];

int cc;

void dfs(int u)
{
  viz[u]=cc;
  for(int i=0;i<(int)G[u].size();i++)
   {
    int v=G[u][i];
    if(!viz[v])
        dfs(v);
   }

}

int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);

    int n,m,u,v,i,j;
    scanf("%d%d",&n,&m);
    for(i=1;i<=m;i++)
    {
     scanf("%d%d",&u,&v);
     G[u].push_back(v);
     G[v].push_back(u);
    }

    for(i=1;i<=n;i++)
        if(!viz[i])
    {
        cc++;
        dfs(i);
    }

    printf("%d\n",cc);

    return 0;
}