#include <bits/stdc++.h>

using namespace std;

const int NMAX = 1e5;

vector <int> edges[NMAX + 1];
int viz[NMAX + 1];

void dfs( int node ) {
    viz[node] = true;
    for ( auto vec : edges[node] ) {
        if ( !viz[vec] ) dfs( vec );
    }
}
int main() {
    ifstream fin( "dfs.in" );
    ofstream fout( "dfs.out" );
    int n, m;
    fin >> n >> m;
    for ( int i = 1, a, b; i <= m; i ++ ) {
        fin >> a >> b;
        edges[a].push_back( b );
        edges[b].push_back( a );
    }
    int cnt = 0;
    for ( int i = 1; i <= n; i ++ ) {
        if ( !viz[i] ) {
            dfs( i );
            cnt ++;
        }
    }
    fout << cnt << '\n';
    return 0;
}