#include <bits/stdc++.h>
#define NMAX 100010

using namespace std;

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

const int oo = 1000000000;
int n, m, x, y, comp;
vector<int> v[NMAX];
bool viz[NMAX];

void dfs(int nod)
{
    viz[nod] = 1;
    for(auto vec:v[nod])
    {
        if(!viz[vec])
            dfs(vec);
    }
}

int main()
{
    fin >> n >> m;
    for(int i=1; i<=m; i++)
    {
        fin >> x >> y;
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i=1; i<=n; i++)
    {
        if(!viz[i]){
            dfs(i);
            comp++;
        }
    }
    fout<<comp;

    return 0;
}