#include <bits/stdc++.h>
using namespace std;
ifstream f("dfs.in");
ofstream g("dfs.out");
const int NMAX=100005;
int n,m,x,y,nrcc,viz[NMAX];
vector<int>v[NMAX];
void dfs(int x,int val)
{
    viz[x]=val;
    for(int i=0; i<v[x].size(); i++)
        if(!viz[v[x][i]])
            dfs(v[x][i],val);
}
int main()
{
    f>>n>>m;
    for(int i=1; i<=m; i++)
    {
        f>>x>>y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i=1; i<=n; i++)
        if(!viz[i])
        {
            nrcc++;
            dfs(i,nrcc);
        }
    g<<nrcc;
    return 0;
}