#include <bits/stdc++.h>
using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
int n,m;
vector<bool>visited(100001);
vector<vector<int>> a;
void dfs(int x){
visited[x]=true;
for(int&i:a[x]){
if(!visited[i])dfs(i);}}
int main(){
fin>>n>>m;
a.resize(n+1);
for(int i=0;i<m;i++){
int x,y;
fin>>x>>y;
a[x].emplace_back(y);
a[y].emplace_back(x);}
int nr=0;
for(int i=1;i<=n;i++){
if(!visited[i]){
nr++;
dfs(i);}}
fout<<nr;
return 0;}