#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <tuple>
#include <cmath>
#include <numeric>
#include <functional>
#include <cassert>
#include <atcoder/segtree>

#define debug_value(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << #x << "=" << x << endl;
#define debug(x) cerr << "line" << __LINE__ << ":<" << __func__ << ">:" << x << endl;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

using namespace std;
typedef long long ll;

template<typename T>
vector<vector<T>> vec2d(int n, int m, T v){
    return vector<vector<T>>(n, vector<T>(m, v));
}

template<typename T>
vector<vector<vector<T>>> vec3d(int n, int m, int k, T v){
    return vector<vector<vector<T>>>(n, vector<vector<T>>(m, vector<T>(k, v)));
}

template<typename T>
void print_vector(vector<T> v, char delimiter=' '){
    if(v.empty()) {
        cout << endl;
        return;
    }
    for(int i = 0; i+1 < v.size(); i++) cout << v[i] << delimiter;
    cout << v.back() << endl;
}

template<typename T>
class Compress{
    public:
    vector<T> data;
    int offset;
    Compress(vector<T> data_, int offset=0): offset(offset){
        set<T> st;
        for(T x: data_) st.insert(x);
        for(T x: st) data.push_back(x);
    };
    int operator[](T x) {
        auto p = lower_bound(data.begin(), data.end(), x);
        assert(x == *p);
        return offset+(p-data.begin());
	}
    T inv(int x){
        return data[x-offset];
    }
    int size(){
        return data.size();
    }
};

using T = tuple<ll, ll, ll>;
const ll inf = 1e18;

ll e(){
    return -inf;
}

ll op(ll x, ll y){
    return max(x, y);
}

using Seg = atcoder::segtree<ll, op, e>;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    int n; cin >> n;
    vector<T> vt(n);
    vector<ll> vv = {-inf, 0, inf};
    for(int i = 0; i < n; i++){
        ll t, x, v; cin >> t >> x >> v;
        vt[i] = T(x+t, -(x-t), v);
        vv.push_back(x-t);
    }
    sort(vt.begin(), vt.end());
    auto cp = Compress<ll>(vv);
    int m = cp.size();
    Seg dp(m);
    dp.set(cp[0], 0);
    for(auto [X, _Y, v]: vt){
        if(X < 0) continue;
        ll Y = -_Y;
        int l = cp[Y];
        ll mx = dp.prod(l, m);
        dp.set(l, mx+v);
    }
    cout << dp.all_prod() << endl;
}