#include <fstream>
#include <vector>
#include <queue>
#include <bitset>

std::ifstream cin( "dfs.in" );
std::ofstream cout( "dfs.out" );

std::vector<int> nod[ 100001 ];
std::bitset<100001> viz;
int n, m;

void DFS( int poz ) {
    viz[ poz ] = 1;
    for( int i = 0; i < nod[ poz ].size(); i++ )
        if( !viz[ nod[ poz ][ i ] ] ) {
            viz[ nod[ poz ][ i ] ] = 1;
            DFS( nod[ poz ][ i ] );
        }
}

int main()
{
    int x, y;
    cin >> n >> m;
    for( int i = 1; i <= m; i++ ) {
        cin >> x >> y;
        nod[ x ].push_back( y );
        nod[ y ].push_back( x );
    }

    int contor = 0;
    for( int i = 1; i <= n; i++ )
        if( !viz[ i ] ) {
            contor++;
            DFS( i );
        }
    cout << contor << '\n';
}