#include <bits/stdc++.h>
#define MAXN 100000

using namespace std;

ifstream fin("dfs.in");
ofstream fout("dfs.out");

void dfs(vector<vector<int>>& graph, int node, bitset<MAXN + 1>& visited) {
    visited[node] = 1;
    for (auto& neighbour : graph[node])
        if (!visited[neighbour])
            dfs(graph, neighbour, visited);
}

int main() {
    int n, m;
    fin >> n >> m;
    vector<vector<int>> graph(n + 1);
    for (int i = 0; i < m; i++) {
        int from, to;
        fin >> from >> to;
        graph[from].push_back(to);
        graph[to].push_back(from);
    }
    
    int result = 0;
    bitset<MAXN + 1> visited;
    for (int i = 1; i <= n; i++) {
        if (!visited[i]) {
            result++;
            dfs(graph, i, visited);
        }
    }

    fout << result << '\n';
    return 0;
}