#include <cstdio>#include <cstring>#include <iostream>#include <map>#include <set>#include <vector>#include <string>#include <queue>#include <deque>#include <bitset>#include <list>#include <cstdlib>#include <climits>#include <cmath>#include <ctime>#include <algorithm>#include <stack>#include <sstream>#include <numeric>#include <fstream>#include <functional>using namespace std;#define MP make_pair#define PB push_back#define lson rt << 1,l,mid#define rson rt << 1 | 1,mid + 1,rtypedef long long LL;typedef unsigned long long ULL;typedef vector<int> VI;typedef pair<int,int> pii;const int INF = INT_MAX / 3;const double eps = 1e-8;const LL LINF = 1e17;const double DINF = 1e60;const int maxn = 1e5 + 10;struct Plank {    int h,l,r,power;    Plank(int h,int l,int r,int power): h(h),l(l),r(r),power(power) {}    bool operator < (const Plank &p) const {        return h < p.h;    }};vector<Plank> plank;int n,Val[maxn << 2],lazy[maxn << 2];LL f[maxn];void pushdown(int rt) {    if(lazy[rt] == -1) return;    Val[rt << 1] = Val[rt << 1 | 1] =         lazy[rt << 1] = lazy[rt << 1 | 1] = lazy[rt];    lazy[rt] = -1;}void update(int rt,int l,int r,int ql,int qr,int v) {    if(ql <= l && qr >= r) {        Val[rt] = v; lazy[rt] = v;    }    else {        int mid = (l + r) >> 1;        pushdown(rt);        if(ql <= mid) update(lson,ql,qr,v);        if(qr > mid) update(rson,ql,qr,v);    }}int query(int rt,int l,int r,int pos) {    if(l == r) return Val[rt];    pushdown(rt);    int mid = (l + r) >> 1;    if(pos <= mid) return query(lson,pos);    else return query(rson,pos);}int main() {    int h,l,r,power,rb;    while(scanf("%d",&n) != EOF) {        plank.clear(); rb = -1;        memset(f,0,sizeof(f));        memset(lazy,-1,sizeof(lazy));        for(int i = 0;i < n;i++) {            scanf("%d%d%d%d",&h,&l,&r,&power);            plank.PB(Plank(h,l,r,power));            rb = max(rb,r);        }        plank.PB(Plank(0,1,rb,0));        sort(plank.begin(),plank.end());        update(1,1,rb,1,rb,0);        for(int i = 1;i <= n;i++) {            int xl = query(1,1,rb,plank[i].l),                xr = query(1,1,rb,plank[i].r);            f[i] = max(f[xl],f[xr]) + plank[i].power;            update(1,1,rb,plank[i].l,plank[i].r,i);        }        LL ans = f[n] + 100; ans = max(ans,-1LL);        cout << ans << endl;    }    return 0;}