#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define F first
#define S second
#define MOD 2000000007
#define ll long long
#define pii pair<int,int>
#define pll pair<long long,long long>
#define ld long double
#define INF 1 << 30
#define NMAX 100005
ifstream in("dfs.in");
ofstream out("dfs.out");

vector<int> v[NMAX];
int viz[NMAX],sol;

void dfs(int nod)
{

    if(viz[nod])
        return;
    viz[nod] = 1;
    for(auto fiu : v[nod])
        if(!viz[fiu])
            dfs(fiu);
}

int main()
{

    int n,m;
    in>>n>>m;
    int a,b;
    for(int i = 1 ; i <= m ; ++i){
        in>>a>>b;
        v[a].pb(b);
        v[b].pb(a);
    }
    for(int i = 1 ; i <= n ; ++i)
    if(!viz[i]){
        dfs(i);
        sol++;
    }
    out<<sol;
    return 0;
}