#include <bits/stdc++.h>
using namespace std;
vector <int> v[100001];
bitset <100001> viz;
int i, n, m, x, y, comp;
void dfs(int k)
{
    viz[k] = 1;
    for(int i = 0; i < v[k].size(); ++ i)
        if(viz[v[k][i]] == 0) dfs(v[k][i]);
}
int main()
{
    ifstream f("dfs.in");
    ofstream g("dfs.out");
    f >> n >> m;
    while(m --)
    {
        f >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    f.close();
    for(i = 1; i <= n; ++ i)
        if(viz[i] == 0)
        {
            comp ++;
            dfs(i);
        }
    g << comp;
    g.close();
    return 0;
}