#include<cstdio>
#include<vector>
#define MAX 100003
using namespace std;
vector<int> v[MAX];
bool viz[MAX];
void dfs(int nod)
{
    viz[nod]=1;
    for(int i=0; i<v[nod].size(); i++)
    {

        if(viz[v[nod][i]]==0)
            dfs(v[nod][i]);
    }
}
int main()
{
    int n,m,cnt=0;
    FILE *fin,*fout;
    fin=fopen("dfs.in","r");
    fout=fopen("dfs.out","w");
    fscanf(fin,"%d%d",&n,&m);
    for(int i = 1; i <= m; i++)
    {
        int x, y;
        fscanf(fin, "%d %d", &x, &y);
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for(int i=1;     i<=n; i++)
    {
        if(viz[i]==0)
        {
            cnt++;
            dfs(i);
        }
    }
    fprintf(fout,"%d",cnt);
}