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#include <cstdio>
#include <vector>
#include <random>
#include <cstdlib>
#include <cassert>

#define REP(i,n) for(int i=0; i<(n); ++i)
#define FOR(i,p,k) for(int i=(p); i<=(k); ++i)

typedef long long LL;

enum { INF = 2000000000 };

template<typename T> inline void checkmin(T &a, T b){ if(a>b) a = b; }
template<typename T> inline void checkmax(T &a, T b){ if(a<b) a = b; }

std::mt19937 rnd(7263847);

struct In
{
  int n;
  std::vector<int> G;
  int & at(int i, int j){ return G[i*n+j]; }
  int operator()(int i, int j) const { return G[i*n+j]; }

  void read()
  {
    scanf("%d",&n); n++;
    G.resize(n*n);
    REP(i,n) at(i,i) = 0;
    REP(i,n-1) FOR(j,i+1,n-1)
    { scanf("%d",&at(i,j)); at(j,i) = at(i,j); }
  }

  void gen(int _n)
  {
    n = _n;
    int x = 1000000000;
    G.resize(n*n);
    REP(i,n) at(i,i) = 0;
    REP(i,n) REP(j,i) at(i,j) = at(j,i) = rnd()%x+1;
  }

  void print()
  {
    REP(i,n){ REP(j,n) printf("%d "); puts(""); }
  }
};

LL go(const In &I)
{
  int n = I.n;
  std::vector<int> D(n); REP(i,n) D[i] = I(0,i);
  LL res = 0;
  while(1)
  {
    int j=-1;
    REP(i,n) if(D[i] && (j==-1 || D[i]<D[j])) j = i;
    if(j==-1) break;
    res += D[j];
    REP(i,n) checkmin(D[i],I(j,i));
  }
  return res;
}

struct Brute
{
  int n;
  std::vector<int> A;
  int & at(int i, int j){ return A[n*i+j]; }

  const In *I;

  LL rec(int i)
  {
    if(i<n)
    {
      LL res = LL(INF)*INF;
      REP(j0,n) FOR(j1,j0+1,n)
      {
        REP(j,n) at(i,j) = 0;
        FOR(j,j0,j1-1) at(i,j) = 1;
        checkmin(res,(*I)(j0,j1)+rec(i+1));
      }
      return res;
    }
    REP(m,1<<n) if(m)
    {
      bool ok = 0;
      REP(j,n)
      {
        bool c = 0; REP(i,n) if(m>>i&1) c ^= at(i,j);
        if(c){ ok = 1; break; }
      }
      if(!ok) return LL(INF)*INF;
    }
    return 0;
  }

  LL run(const In &_I)
  {
    I = &_I;
    n = I->n-1;
    A.resize(n*n);
    return rec(0);
  }
};

void test()
{
  REP(_,100){ In I; I.gen(1000); assert(go(I)>=999); }
  puts("crash test complete");
  for(int c=0;; c++)
  {
    In I; I.gen(6);
    Brute brute;
    LL b = brute.run(I);
    LL s = go(I);
    if(b!=s)
    {
      printf("ERROR (s=%lld; b=%lld)\n",s,b);
      I.print();
      exit(1);
    }
    printf("ok (s=%lld; b=%lld)\n",s,b);
  }
}

int main()
{
  //test();
  In I; I.read();
  printf("%lld\n",go(I));
  return 0;
}