#include <bits/stdc++.h>
using namespace std;
int viz[100005],i,m,n,nr,x,y;
vector <int> v[100005];
void dfs(int nod)
{
    int i;
    viz[nod]=1;
    for(i=0;i<v[nod].size();i++)
        if(viz[v[nod][i]]==0)dfs(v[nod][i]);
}
int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(i=1;i<=m;i++)
    {
        scanf("%d%d",&x,&y);
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(i=1;i<=n;i++)
    {
        if(viz[i]==0)
        {
            dfs(i);
            nr++;
        }
    }
    printf("%d",nr);
    return 0;
}