#include<iostream>
#include<fstream>
#include<vector>

using namespace std;

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

const int maxN=100001;
const int maxM=200001;

int n,m, compConex;
vector<int> graph[maxN];
int visited[maxN];

void DFS(int node)
{   
    int i;
    visited[node]=1;

    for(auto vecin:graph[node])
        if(visited[vecin]==-1)
            DFS(vecin);
}

int main()
{   
    int i,x,y;
    fin>>n>>m;

    for(i=1; i<=m; i++)
    {
        fin>>x>>y;
        graph[x].push_back(y);
        graph[y].push_back(x);
    }

     for(i=1; i<=n; i++)
        visited[i]=-1;

    for(i=1;i<=n; i++)
        if(visited[i]==-1)
        {
            compConex+=1;
            DFS(i);
        }    
fout<<compConex;

}