#include <iostream>
#include <vector>
#include <queue>
#define maxn 100010

using namespace std;

int viz[maxn],cnt,n,m;
vector<int> g[maxn];

void dfs (int nod) {
    int i;

    viz[nod] = 1;

    for (i=0; i<g[nod].size(); i++) {
        if (viz[g[nod][i]] == 0) {
            dfs(g[nod][i]);
        }
    }
}


int main()
{
    int i,x,y;

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

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

    //Se citesc muchiile
    for (i=0; i<m; i++) {
        scanf("%d %d", &x, &y);
        g[x].push_back(y);
        g[y].push_back(x);
    }

    //Se ver daca nodul a mai fost vizitat
    for (i=1; i<=n; i++) {
        if (viz[i] == 0) {
            cnt++;
            dfs(i);
        }
    }

    //Se afiseaza rezultatul
    printf("%d", cnt);

    return 0;
}