#include <cstdio>
#include<vector>
#include<algorithm>
using namespace std;
vector<int> G[100005];
int viz[100005];

int nr;
int 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 max=0,n,m,i,u,v;
    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]==0)
        {
           dfs(i);
            nr++;
        }
    }
    printf("%d",nr);
    return 0;
}