#include <bits/stdc++.h>

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");


int const N = 100010;
vector<vector<int>> path(N);
bitset<N> visited;


void dfs(int vert);

int main()
{
    int vertices,edges,conComponents=0;
    fin>>vertices>>edges;

    int x,y;
    for(;edges;edges--)
    {
        fin>>x>>y;
        path[x].push_back(y);
        path[y].push_back(x);
    }
    for(int i=1;i<=vertices;i++)
    {
        if(!visited[i])
        {
            conComponents++;
            visited[i]=1;
            dfs(i);
        }
    }
    fout<<conComponents<<'\n';
    return 0;
}
void dfs(int vert)
{
    for(int i=0;i<path[vert].size();i++)
        if(!visited[path[vert][i]])
        {
            visited[path[vert][i]]=1;
            dfs(path[vert][i]);
        }
}