#include <bits/stdc++.h>

using namespace std;

int n, m;
vector<vector<int>> edges;
vector<bool> visited;

void dfs(int start) {
    visited[start] = true;
    for(const auto& edge : edges[start]) {
        if(!visited[edge]) {
            dfs(edge);
        }
    }
}

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

    scanf("%d %d", &n, &m);
    
    edges.resize(n);
    visited.assign(n, false);

    for(int i = 1; i <= m; ++i) {
        int from, to;
        scanf("%d %d", &from, &to);
        edges[from].push_back(to);
        edges[to].push_back(from);
    }
    
    int connectedComponents = 0;
    for(int i = 0; i < n; ++i) {
        if(!visited[i]) {
            dfs(i);
            ++connectedComponents;
        }
    }

    cout << connectedComponents << endl;

    return 0;
}