#include<iostream>

#include<cstdio>

#include<algorithm>

#include<vector>

#include<cstring>

#include<map>

#include<set>

#include<queue>

#include<bitset>

#include<utility>

#include<functional>

#include<iomanip>

#include<sstream>

#include<ctime>

#include<cassert>

#define A first

#define B second

#define mp make_pair

#define pb push_back

#define pw(x) (1ll << (x))

#define sz(x) ((int)(x).size())

#define all(x) (x).begin(),(x).end()

#define rep(i,l,r) for(int i=(l);i<(r);i++)

#define per(i,r,l) for(int i=(r);i>=(l);i--)

#define FOR(i,l,r) for(int i=(l);i<=(r);i++)

#define eps 1e-9

#define PIE acos(-1)

#define cl(a,b) memset(a,b,sizeof(a))

#define fastio ios::sync_with_stdio(false);cin.tie(0);

#define lson l , mid , ls

#define rson mid + 1 , r , rs

#define ls (rt<<1)

#define rs (ls|1)

#define INF 0x3f3f3f3f

#define lowbit(x) (x&(-x))

#define sqr(a) a*a

#define ll long long

#define ull unsigned long long

#define vi vector<int>

#define pii pair<int, int>

#define dd(x) cout << #x << " = " << (x) << ", "

#define de(x) cout << #x << " = " << (x) << "\n"

#define endl "\n"

using namespace std;

#define pll pair<ll,ll>

const int maxn=1e5+;

ll n,d[maxn<<];

ll tot;

vector<int>v;

//**********************************

struct Node{

    ll x,y,v;

    bool operator<(const Node& rhs){

        if(x!=rhs.x)return x<rhs.x;

        return y>rhs.y;

    }

}node[maxn];

void update(ll x,ll val)

{

    while(x<=sz(v)){

        d[x]=max(d[x],val);

        x+=lowbit(x);

    }

}

ll query(int x)

{

    ll ans=;

    while(x){

        ans=max(ans,d[x]);

        x-=lowbit(x);

    }

    return ans;

}

inline int getid(int x){return lower_bound(all(v),x)-v.begin()+;}

//**********************************

map<pll,ll>Mp;

//**********************************

int main()

{

    fastio;

    cin>>n;

    map<pll,ll>::iterator it;

    rep(i,,n){

        cin>>node[i].x>>node[i].y>>node[i].v,v.pb(node[i].y);

        pii PII=mp(node[i].x,node[i].y);

        it=Mp.find(PII);

        if(it!=Mp.end())node[i].v+=Mp[PII],Mp.erase(PII);

        Mp.insert(mp(PII,node[i].v));

    }

    sort(all(v));v.erase(unique(all(v)),v.end());

    rep(i,,n)node[i].y=getid(node[i].y);

    ll tot=;

    sort(node,node+n);

    ll ans=;

    rep(i,,n){

            ll tmp;

            tmp=query(node[i].y-)+node[i].v;

            ans=max(ans,tmp);

            update(node[i].y,tmp);

    }

    cout<<ans<<endl;

    return ;

}