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

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

vector<int> graph[100002];
int visited[100002];

void dfs(int node) {
    visited[node]=1;
    for (auto i:graph[node]) {
        if (visited[i]==1) continue;
        dfs(i);
    }
}

int main() {
    int n,m;
    in>>n>>m;

    while(m--) {
        int x,y;
        in>>x>>y;
        graph[x].push_back(y);
        graph[y].push_back(x);
    }

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