#include <bits/stdc++.h>

using namespace std;
ifstream fin("dfs.in");
ofstream fout("dfs.out");
#define SIZE 100001
#define cin fin
#define cout fout

int n, m;
bool v[SIZE];
vector<int> a[SIZE];
int rez;

void dfs(int p){
    // int s=a[p].size();
    v[p]=1;
    for(auto i: a[p]){
        if(!v[i]){
            dfs(i);
        }
    }
}

int main()
{
    cin>>n>>m;
    for(int i=1; i<=m; i++){
        int x, y;
        cin>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    for(int k=1; k<=n; k++){
        if(!v[k]){
            dfs(k);
            rez++;
        }
    }
    cout<<rez;

    return 0;
}