#include <cstdio>
#include <vector>
using namespace std;

vector <int> G[100005];
int viz[100005],comp;

void dfs(int i)
{
    int v;
    for(int j=0;j<(int)G[i].size();j++)
    {
        v=G[i][j];

        if(viz[v]==0)
        {
            viz[v]=comp;
            dfs(v);
        }
    }
}

int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);

    int n,m,a,b,i;

    scanf("%d%d",&n,&m);

    for(i=1;i<=m;i++)
    {
        scanf("%d%d",&a,&b);
        G[a].push_back(b);
        G[b].push_back(a);
    }

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

    printf("%d\n",comp);

    return 0;
}