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

int n, m, x, y, a[100][100], g[100];
bool viz[100];
int gmax=0, ki=0, kc=0, nmax=0, nrn=0;

void dfs(int nod){
    viz[nod]=1;
    for(int j=1;j<=n;j++){
        if (viz[j]==0 && a[nod][j]==1) dfs(j);
    }
}
int main(){
	ifstream cin("dfs.in");
	ofstream cout("dfs.out");
cin>>n>>m;
    for (int i=1;i<=m;i++){
        cin>>x>>y;
        a[x][y]=1;
        a[y][x]=1;
    }
for (int i=1;i<=n;i++){ if(!viz[i]) dfs(i),kc++;}
 cout<<kc;
 
}