#include <cstdio>
#include <vector>
#include <algorithm>

using namespace std;

const int NMAX = 100005;

vector <int> G[NMAX];
vector <int> viz;
int cc;

void dfs(int u) {
    int n = G[u].size(), v;
    viz[u] = cc;
    for(int j = 0; j < n; ++ j) {
        v = G[u][j];
        if(!viz[v]) {
            dfs(v);
        }
    }
}

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

    int n, m, u, v;

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

    for(int i = 1; i <= m; ++ i) {
        scanf("%d%d", &u, &v);
        G[u].push_back(v);
        G[v].push_back(u);
    }

    viz.assign(n + 1, 0);

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

    printf("%d\n", cc);

    return 0;
}