#include <iostream>
#include <fstream>
#include <vector>
#include <stack>
using namespace std;


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

vector<int> g[100001];
int n, m;
int viz[100001]={0};
vector<int> parcurgere;
stack<int> st;
int nrc=0;


void dfs(int nod) {
viz[nod]=nrc;
st.push(nod);

for(auto x: g[nod]) {
    if(viz[x]==0) {
        dfs(x);
    }
}


}

int main()
{
    fin>>n>>m;
    for(int i=1; i<=m; i++) {
        int x, y;
        fin>>x>>y;
        g[x].push_back(y);
        g[y].push_back(x);
    }

     for(int i=1; i<=n; i++) {
        if(viz[i]==0) {
            nrc++;
            dfs(i);
        }
    }

    fout<<nrc;
    return 0;
}