Kayaking codeforces

#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
using namespace std;
int main()
{
    ios_base::sync_with_stdio(false);cin.tie(NULL);
    int n,x,sum=0;cin>>n;
    vector<int>a;
    set<int>ans;
    for(int i=0;i<(2*n);i++){cin>>x;a.push_back(x);}
    sort(a.begin(),a.end());
    for(int i=0;i<(2*n-1);i++)
    {
        for(int j=i+1;j<2*n;j++)
        {
            sum=0;
            for(int k=0;k<(2*n-1);)
            {
                if (k==i || k==j)k++;
                else if ((k+1)!=i || (k+1)!=j){sum+=(a[k+1]-a[k]);k+=2;}
                else if ((k+2)==j){sum+=(a[k+3]-a[k]);k+=4;}
                else if ((k+1)==i){sum+=(a[k+2]-a[k]);k+=3;}
            }
            ans.insert(sum);
        }
    }
    cout<<*ans.begin()<<endl;
}