#include <bits/stdc++.h>

using namespace std;

ifstream fin ("dfs.in");
ofstream fout ("dfs.out");

vector <int> gf[100005];

int n, m, i, x, y, fv[100005], cc;

void dfs ( int nod )
{
    if ( fv[nod] == 0 )
    {
        fv[nod] = 1;
        for ( int j = 0 ; j < gf[nod].size() ; j++ )
        {
            dfs( gf[nod][j] );
        }

    }
}

int main ()
{
    fin>>n>>m;

    for (i = 1; i <= m ; i++)
    {
        fin>>x>>y;
        gf[x].push_back(y);
        gf[y].push_back(x);
    }

    for ( i = 1; i <= n; i++ )
    {
        if ( fv[i] == 0 )
        {
           cc++;
           dfs(i);
        }
    }

    fout<<cc;

    return 0;
}