#include <fstream>
#include <vector>

using namespace std;

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

const int N = 1e5 + 1;
vector <int> a[N];
int viz[N], cc;

void dfs(int x)
{
    viz[x] = cc;
    for(auto y : a[x])
    {
        if(viz[y] == 0)
            dfs(y);
    }
}

int main()
{
    int n, m, i, x, y;
    fin >> n >> m;
    for(i = 1; i <= m; i++)
    {
        fin >> x >> y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    for(i = 1; i <= n; i++)
    {
        if(viz[i] == 0)
        {
            cc++;
            dfs(i);
        }
    }
    fout << cc;
    return 0;
}