#include <cstdio>
#include<vector>
using namespace std;
vector <int>G[100001];
bool viz[100001];
void dfs(int nod)
{
    int i;
    viz[nod]=1;
    for(i=0;i<G[nod].size();i++)
      if(!viz[G[nod][i]])
        dfs(G[nod][i]);
}
int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    int n,m,i,a,b,cnt=0;
    scanf("%d%d",&n,&m);
    for(i=1;i<=m;i++)
    {
    scanf("%d%d",&a,&b);
    G[a].push_back(b);
    G[b].push_back(a);
    }
    for(i=1;i<=n;i++)
    if(viz[i]==0){
      dfs(i);
      cnt++;
    }
    printf("%d",cnt);
    return 0;
}