#include<bits/stdc++.h>
using namespace std;

const int N = 100009;

ifstream in ("dfs.in");
ofstream out("dfs.out");
// auto& in = cin;
// auto& out = cout;

int n;
vector<vector<int>> adj(N, vector<int>());
bool visited[N];

void read() {
	int m, x, y;
	in>>n>>m;
	for(int i = 0; i < m; i++) {
		in>>x>>y;
		adj[x].push_back(y);
		adj[y].push_back(x);
	}
}

void dfs(int crt) {
	if(visited[crt])	return;
	visited[crt] = true;
	for(auto neighbor : adj[crt])
		dfs(neighbor);
}

int main(){
	read();
	int comps = 0;
	for(int i = 1; i <= n; i++)
		if(!visited[i]) {
			comps++;
			dfs(i);
		}
	out<<comps<<endl;
	return 0;
}