#include <bits/stdc++.h>

using namespace std;

const int MAXN = 100005;

vector<int> graf[MAXN];
bool viz[MAXN];

void dfs(int nod){
    if(viz[nod])
        return;
    viz[nod] = 1;
    for(auto x : graf[nod])
        dfs(x);
}

int main()
{
    ifstream fin("dfs.in");
    ofstream fout("dfs.out");
    int n, m, x, y;
    fin >> n >> m;
    while(m){
        fin >> x >> y;
        graf[x].push_back(y);
        graf[y].push_back(x);
        m--;
    }
    int cnt = 0;
    for(int i = 1; i <= n; ++i){
        if(!viz[i]){
            cnt++;
            dfs(i);
        }
    }
    fout << cnt;
    return 0;
}