#include <iostream>
#include <vector>
#include <queue>

using namespace std;

int visited[1000]; 
vector<int> c[1000];

void counting_is_good(int i) {
    queue<int> q;
    q.push(i);
    visited[i] = true;

    while (!q.empty()) {
        int cc = q.front();
        q.pop();

        for (int i = 0; i < c[cc].size(); i++) {
            int next = c[cc][i];
            
            if (!visited[next]) {
                visited[next] = 1; 
                q.push(next); 
            }
        }
    }
}

int main() {
    int cnt = 0;
    int n, m;
    cin >> n >> m;

    for (int i = 0; i < m; i++) {
        int arr, raa;
        cin >> arr >> raa;
        c[arr].push_back(raa);
        c[raa].push_back(arr);
    }

    for (int i = 1;i <= n; i++) {
        if (!visited[i]) { 
            counting_is_good(i);
            cnt++;   
        }
    }

    cout << cnt;

    return 0;
}
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//    |   |_____________________|      |
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