#include <cstdio>
#include <vector>
using namespace std;

int n, m, i, x, y, viz[100005] {}, count;
vector<int> G[100005];

void dfs(int nod) {
    if(viz[nod] == 0) {
        viz[nod] = 1;
        for(int j = 0; j < G[nod].size(); ++j)
            dfs(G[nod][j]);
    }
}

int main() {
    freopen("dfs.in", "r", stdin);
    freopen("dfs.out", "w", stdout);
    scanf("%d%d", &n, &m);
    for(i = 1; i <= m; ++i) {
        scanf("%d%d", &x, &y);
        G[x].push_back(y);
        G[y].push_back(x);
    }

    for(i = 1; i <= n; ++i)
        if(viz[i] == 0) {
            ++count;
            dfs(i);
        }

    printf("%d", count);
}