#include <iostream>
#include <cstdio>
#include <vector>
#include <bitset>

using namespace std;

vector <int> g[100005];
bitset <100005> viz;

int n,m,rez, x, y;

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

int main()
{
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);

    scanf("%d %d", &n, &m);

    for(int i=0;i<m;++i){
        scanf("\n%d %d", &x, &y);
        g[x].push_back(y);
        g[y].push_back(x);
    }

    for(int i=1;i<=n;++i)
        if(!viz[i]){
            ++rez;
            dfs(i);
        }

    cout<<rez;

    return 0;
}