#include<cstdio>
#include<vector>
using namespace std;
#define MAX_N   100010
vector<int> L[MAX_N];
bool v[MAX_N];
int n, m, cnt;
void dfs(int nod) {
    v[nod] = 1;
    for (vector<int>::iterator it = L[nod].begin(); it != L[nod].end(); it++)
        if (v[*it] == 0)
            dfs(*it);
}
void file_init() {
    if (freopen("dfs.in", "rt", stdin));
    if (freopen("dfs.out", "wt", stdout));
}
void file_close() {
    fclose(stdin);
    fclose(stdout);
}
int main() {
    file_init();
    int x, y;
    if (scanf("%d %d", &n, &m));
    for (int i=1; i<=m; ++i) {
        if (scanf("%d %d", &x, &y));
        L[x].push_back(y);
        L[y].push_back(x);
    }
    for (int i=1; i<=n; ++i) if (v[i] == 0) {
        ++cnt;
        dfs(i);
    }
    printf ("%d ", cnt);
    file_close();
    return 0;
}