#include <bits/stdc++.h>

using namespace std;

ifstream in("dfs.in");
ofstream out("dfs.out");
vector<int> v[1000005];
int n,m,cnt;
bool viz[100005];

void dfs(int ns)
{
  viz[ns] = true;
  for (int i = 0;i < v[ns].size();++i)
       if (viz[v[ns][i]] == false)
           {viz[v[ns][i]] = true;
           dfs(v[ns][i]);}
}

int main()
{
    in>>n>>m;
    for (int i = 1;i <= m;++i)
        {int x,y;
        in>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);}
     for (int i = 1;i <= n;++i)
          if (viz[i] == false)
              {dfs(i);
           ++cnt;}
    out<<cnt;
    return 0;
}