//Lib
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<ctime>
 
#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<queue>
#include<stack>
#include<set>
#include<map>
using namespace std;
//Macro
#define rep(i,a,b)  for(int i=a,tt=b;i<=tt;++i)
#define drep(i,a,b) for(int i=a,tt=b;i>=tt;--i)
#define erep(i,e,x) for(int i=x;i;i=e[i].next)
#define irep(i,x)   for(__typeof(x.begin()) i=x.begin();i!=x.end();i++)
#define brep(i,x)   for(int i=x;i<=limit;i+=lowbit(i))
#define bdrep(i,x)  for(int i=x;i>0;i-=lowbit(i))
#define read()  (strtol(ipos,&ipos,10))
#define sqr(x)  ((x)*(x))
#define pb  push_back
#define PS  system("pause");
typedef long long   ll;
typedef pair<int,int> pii;
const int oo=~0U>>1;
const double inf=1e100;
const double eps=1e-6;
string name="", in=".in", out=".out";
//Var
struct BIT
{
    int s[200008],limit;
    inline int lowbit(int x){return x&-x;}
    void Set(int l){memset(s,0,sizeof s);limit=l;}
    void Update(int x,int delta)
    {
        brep(i,x)s[i]+=delta;
    }
    int Get(int x,int y)
    {
        int ret=0;
        bdrep(i,y)ret+=s[i];
        bdrep(i,x)ret-=s[i];
        return ret;
    }
}T;
int n,num[200008],vis[200008],ans;
void Work()
{
    scanf("%d",&n);
    T.Set(n<<2);
    rep(i,1,n<<1)
        scanf("%d",num+i);
    rep(i,1,n<<1)
    {
        if(!vis[num[i]])
            T.Update(i,1),vis[num[i]]=i;
        else
        {
            ans+=T.Get(vis[num[i]]-1,i)-1;
            T.Update(vis[num[i]],-1);
        }
    }
    cout<<ans<<endl;
}
int main()
{
//  freopen((name+in).c_str(),"r",stdin);
//  freopen((name+out).c_str(),"w",stdout);
//  Init();
    Work();
    return 0;
}