#include <iostream>
#include <vector>
#include <cstdio>
#include <cstdlib>

using namespace std;

#define pb push_back
const int maxn = 1e5 + 5;

int n, m;
vector<int> arr[maxn];
bool visited[maxn];

void dfs(int node) {
    visited[node] = true;

    for(int i = 0; i < arr[node].size(); i++)
        if (!visited[arr[node][i]])
            dfs(arr[node][i]);
}

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

    cin >> n >> m;
    for (int i = 0; i < m; i++) {
        int x, y;
        cin >> x >> y;
        arr[x].pb(y);
        arr[y].pb(x);
    }

    int cnt = 0;
    for (int i = 1; i <= n; ++i)
    if (!visited[i]) {
        dfs(i);
        ++cnt;
    }
    cout << cnt;

    return 0;
}