#include <fstream>
#include <queue>

using namespace std;

ifstream f("dfs.in");
ofstream g("dfs.out");

int n;
bool A[101][101], viz[101];

queue<int> Q;

void citire()
{
    int m, x, y;
    f >> n >> m;
    while(m--)
    {
        f >> x >> y;
        A[x][y] = A[y][x] = 1;
    }
}

void BFS(int nod)
{
    Q.push(nod);
    viz[nod] = 1;

    while(!Q.empty())
    {
        int crt = Q.front();
        Q.pop();

        for(int i = 1; i <= n; i++)
            if(A[crt][i] == 1 && viz[i] == 0)
            {
                viz[i] = 1;
                Q.push(i);
            }
    }
}

int main()
{
    int nrCC = 0;
    citire();

    for(int i = 1; i <= n; i++)
        if(viz[i] == 0)
        {
            nrCC++;
            BFS(i);
        }

    g << nrCC;

    f.close();
    g.close();
    return 0;
}