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

int main() {
    int n;
    cin>>n;
    vector<int> b;
    for(int i=0;i<2*n;i++) {
        int temp;
        cin>>temp;
        b.push_back(temp);
    }
    int count1=0;
    while(b.size()!=0) {
        int val;
        for(int i=1;i<b.size();i++) {
            if(b[i]==b[0]){
                val=i;
                break;
            }
        }
        if(val!=1)
       count1+=(val-1);
       b.erase(b.begin()+val);
       b.erase(b.begin());
    }
    cout<<count1<<endl;
}