# include <fstream>
# include <vector>
# define Nmax 100005
std::ifstream f("dfs.in"); std::ofstream g("dfs.out");
std::vector<int> a[Nmax];
int n, m, x, y, nr, viz[Nmax]; //, c[Nmax]; tin c pentru afisare. 
void dfs(int p)
{int q;
 viz[p]=1; //c[p] = nr;
 for(unsigned int i=0; i<a[p].size(); i++) 
	 {q=a[p][i];
	  if(!viz[q]) dfs(q);
	 }
}
int main()
{
 f>>n>>m;
 for(int i = 1; i <= m; ++i) {f>>x>>y; a[x].push_back(y); a[y].push_back(x);}
 for(int i=1; i<=n; ++i ) 
	if(!viz[i]) {nr++; dfs(i);}
 /*std::cout<<"In graf sunt "<<nr<<" componente conexe\n";
 for(int cmp=1;cmp<=nr;cmp++){
	 std::cout<<"Componenta "<<cmp<<": ";
	 for(int i=1;i<=n;i++) if(c[i] == cmp) std::cout<<i<<" ";
	 std::cout<<std::endl;
 }*/
 g<<nr<<"\n"; g.close();
 return 0;
}