#include<bits/stdc++.h>
using namespace std;
// define
//bool M1;
//#define execute cerr << " Time: " << fixed << setprecision(6) << (1.0 * clock() / CLOCKS_PER_SEC) << "s\n";
//#define memory cerr << abs(&M2 - &M1)/1024.0/1024 << " MB" << "\n"
#define ll long long
#define ii pair <int , int>
#define iii pair <int , ii>
#define se second
#define fi first
#define all(v) (v).begin() , (v).end()
#define Unique(v) sort(all(v)) , v.resize(unique(all(v)) - v.begin())
#define bit(x,i) (((x) >> (i)) & 1LL)
#define flip(x,i) ((x) ^ (1LL << (i)))
#define ms(d,x) memset(d , x , sizeof(d))
#define exist __exist
#define ends __ends
#define visit visited
#define left __left
#define right __right
#define prev __prev
#define next __next
#define sitingfake 1
#define orz 1
//constant
const long long mod = 1e9 + 7;
const long long linf = 4557430888798830399LL;
const long long nlinf = -4485090715960753727LL;
const int inf = 1061109567;
const int ninf = -1044266559;
const int dx[] = {0 , -1 , 0 , 1};
const int dy[] = {-1 , 0 , 1 , 0};
template<typename T> bool maximize(T &a, const T &b)
{
if(a < b) {a = b; return 1;}
return 0;
}
template<typename T> bool minimize(T &a, const T &b)
{
if(a > b) {a = b; return 1;}
return 0;
}
void Plus(ll & a ,ll b)
{
b %= mod;
a += b;
if(a < 0) a += mod;
a %= mod;
return;
}
void Mul(ll & a, ll b)
{
(a *= (b % mod)) %= mod;
return;
}
//code
const int maxn = 150005;
int n;
struct Beaver
{
int x , y , z;
}a[maxn];
namespace sub2
{
struct BIT
{
int bit[4005];
BIT()
{
ms(bit , 0);
}
void up(int x , int val)
{
for(;x <= n; x += (x & -x))
{
bit[x] = max(bit[x] , val);
}
}
int get(int x)
{
int ans = 0;
for(;x > 0; x -= (x & -x))
{
ans = max(ans , bit[x]);
}
return ans;
}
};
vector <int> py , pz;
int posy[4004] , posz[4004];
void compress()
{
for(int i = 1; i <= n; i++)
{
py.push_back(a[i].y);
pz.push_back(a[i].z);
}
Unique(py);
Unique(pz);
for(int i = 1; i <= n; i++)
{
posy[i] = lower_bound(all(py) , a[i].y) - py.begin() + 1;
posz[i] = lower_bound(all(pz) , a[i].z) - pz.begin() + 1;
}
}
bool cmp(Beaver &a , Beaver &b)
{
return a.x < b.x;
}
void solve()
{
sort(a + 1 , a + n + 1 , cmp);
compress();
BIT bitY , bitZ;
int it = 1;
int ans = -1;
for(int i = 3; i <= n; i++)
{
while(it < i && a[it].x < a[i].x)
{
bitY.up(posy[it] , a[it].z);
bitZ.up(posz[it] , a[it].y);
it++;
}
for(int j = i - 1; j >= 1; j--)
{
if(a[i].x > a[j].x)
{
if(a[j].y > a[i].y)
{
int val = bitY.get(posy[j] - 1);
if(val > max(a[i].z , a[j].z))
{
ans = max(ans , a[i].x + a[j].y + val);
}
}
if(a[j].z > a[i].z)
{
int val = bitZ.get(posz[j] - 1);
if(val > max(a[i].z , a[j].z))
{
ans = max(ans , a[i].x + a[j].z + val);
}
}
}
}
}
cout << ans;
}
}
namespace sub5
{
int MinY[4040] , MinZ[4040];
vector <ii> Point[4004];
bool approve()
{
for(int i = 1; i <= n; i++)
{
if(a[i].x > 300) return 0;
else if(a[i].y > 300) return 0;
else if(a[i].z > 300) return 0;
}
return 1;
}
void solve()
{
for(int i = 1; i <= n; i++)
{
Point[a[i].x].push_back({a[i].y , a[i].z});
}
for(int i = 1; i <= 300; i++)
{
sort(all(Point[i]));
}
ms(MinY , 0x3f);
ms(MinZ , 0x3f);
int ans = 0;
for(int x = 1; x <= 300; x++)
{
int mi = inf;
int it = 0;
if(Point[x].empty()) continue;
for(int y = 1; y <= 300; y++)
{
while(it < Point[x].size() && Point[x][it].fi < y)
{
mi = min(mi , Point[x][it].se);
++it;
}
int LimZ = max(mi , MinZ[y]);
for(int z = LimZ + 1; z <= 300; z++)
{
if(MinY[z] < y)
{
ans = max(ans , x + y + z);
}
}
}
for(ii it : Point[x])
{
MinY[it.se] = min(MinY[it.se] , it.fi);
MinZ[it.fi] = min(MinZ[it.fi] , it.se);
}
}
cout << ans;
}
}
namespace sub7
{
int idx[maxn] , idy[maxn] , idz[maxn];
int numx , numy , numz;
void compress()
{
vector <int> px , py , pz;
for(int i = 1; i <= n; i++)
{
px.push_back(a[i].x);
py.push_back(a[i].y);
pz.push_back(a[i].z);
}
Unique(px);
Unique(py);
Unique(pz);
for(int i = 1; i <= n; i++)
{
a[i].x = lower_bound(all(px) , a[i].x) - px.begin() + 1;
a[i].y = lower_bound(all(py) , a[i].y) - py.begin() + 1;
a[i].z = lower_bound(all(pz) , a[i].z) - pz.begin() + 1;
}
numx = px.size();
numy = py.size();
numz = pz.size();
for(int i = 0; i < px.size(); i++)
{
idx[i + 1] = px[i];
}
for(int i = 0; i < py.size(); i++)
{
idy[i + 1] = py[i];
}
for(int i = 0; i < pz.size(); i++)
{
idz[i + 1] = pz[i];
}
}
vector <ii> Point[maxn];
bool cmp(ii &a , ii &b)
{
return a.se < b.se;
}
struct BIT
{
int bit[maxn];
BIT ()
{
ms(bit , 0);
}
void up(int x , int val)
{
for(;x <= n; x += (x & -x))
{
bit[x] = max(bit[x] , val);
}
}
int get(int x)
{
int ans = 0;
for(;x > 0; x -= (x & -x))
{
ans = max(ans , bit[x]);
}
return ans;
}
};
struct BITPAIR
{
vector <ii> bit;
int sz = 0;
BITPAIR (int n)
{
sz = n;
bit.resize(n + 3);
for(int i = 0; i <= sz; i++) bit[i] = {0 , 0};
}
void up(int x , int pos , int val)
{
for(;x > 0; x -= (x & -x))
{
bit[x] = max(bit[x] , {val , pos});
}
}
ii get(int x)
{
ii ans = {0 , 0};
for(;x <= sz; x += (x & -x))
{
ans = max(ans , bit[x]);
}
return ans;
}
};
void solve()
{
//cout << 11111 << endl;
compress();
for(int i = 1; i <= n; i++)
{
Point[a[i].x].push_back({a[i].y , a[i].z});
}
int ans = -1;
BIT bitY , bitZ;
BITPAIR BY(n) , BZ(n);
for(int x = 1; x <= numx; x++)
{
sort(all(Point[x]));
for(ii it : Point[x])
{
ii val = BY.get(it.fi + 1);
if(val.se > it.se)
{
ans = max(ans , idx[x] + idy[val.se] + idz[val.fi]);
}
val = BZ.get(it.se + 1);
if(val.se > it.fi)
{
ans = max(ans , idx[x] + idy[val.fi] + idz[val.se]);
}
}
int it = 0;
for(int j = 0; j < Point[x].size(); j++)
{
while(it < j && Point[x][it].fi < Point[x][j].fi)
{
bitY.up(Point[x][it].fi , Point[x][it].se);
it++;
}
int Max = bitY.get(Point[x][j].fi - 1);
if(Max > Point[x][j].se)
{
BY.up(Point[x][j].fi , Point[x][j].fi , Max);
}
}
for(int j = it ; j < Point[x].size(); j++)
{
bitY.up(Point[x][it].fi , Point[x][it].se);
}
sort(all(Point[x]) , cmp);
it = 0;
for(int j = 0; j < Point[x].size(); j++)
{
while(it < j && Point[x][it].se < Point[x][j].se)
{
bitZ.up(Point[x][it].se , Point[x][it].fi);
it++;
}
int Max = bitZ.get(Point[x][j].se - 1);
if(Max > Point[x][j].fi)
{
BZ.up(Point[x][j].se , Point[x][j].se , Max);
}
}
for(int j = it ; j < Point[x].size(); j++)
{
bitZ.up(Point[x][it].se , Point[x][it].fi);
}
}
cout << ans;
}
}
void solve(void)
{
cin >> n;
for(int i = 1; i <= n; i++)
{
cin >> a[i].x >> a[i].y >> a[i].z;
}
if(n <= 4000) return sub2 :: solve();
if(sub5 :: approve()) return sub5 :: solve();
sub7 :: solve();
}
/**
**/
//bool M2;
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
#define task ""
if(fopen(task".inp","r"))
{
freopen(task".inp","r",stdin);
freopen(task".out","w",stdout);
}
int tc = 1;
// cin >> tc;
while(tc--) solve();
// execute;
// memory;
}
