#include <cstdio>
#include <vector>

using namespace std;
vector <int> v[100005];
int n,m,i,x,y,cmp,viz[100005];

void dfs(int x)
{
    int i;
    viz[x]=1;
    for (i=0; i<v[x].size(); i++)
        if (viz[v[x][i]]==0)
        dfs(v[x][i]);
}

int main()
{
    freopen("dfs.in","r",stdin);
    freopen("dfs.out","w",stdout);
    scanf("%d%d",&n,&m);
    for (i=1; i<=m; i++)
    {
        scanf("%d%d",&x,&y);
        v[x].push_back(y);
        v[y].push_back(x);
    }
    for (i=1; i<=n; i++)
        if (viz[i]==0)
    {
        cmp++;
        dfs(i);
    }
    printf("%d\n",cmp);
    return 0;
}