class SegTree():
    def __init__(self, n, e, ope, lst=[]):
        self.N0 = 2 ** (n - 1).bit_length()
        self.e = e
        self.ope = ope
        self.data = [e] * (2 * self.N0)
        if lst:
            for i in range(n):
                self.data[self.N0 + i] = lst[i]
            for i in range(self.N0 - 1, 0, -1):
                self.data[i] = self.ope(self.data[2 * i], self.data[2 * i + 1])
    
    def f5(self):
        for i in range(self.N0 - 1, 0, -1):
            self.data[i] = self.ope(self.data[2 * i], self.data[2 * i + 1])
                
    def update(self, i, x): #a_iの値をxに更新
        i += self.N0
        self.data[i] = x
        while i > 1:
            i >>= 1
            self.data[i] = self.ope(self.data[2 * i], self.data[2 * i + 1])
    
    def add(self, i, x):
        self.update(i, x + self.get(i))
    
    def query(self, l, r): #区間[l, r)での演算結果
        if r <= l:
            return self.e
            
        lres = self.e
        rres = self.e
        l += self.N0
        r += self.N0
        while l < r:
            if l & 1:
                lres = self.ope(lres, self.data[l])
                l += 1
            if r & 1:
                r -= 1
                rres = self.ope(self.data[r], rres)
            l >>= 1
            r >>= 1
        return self.ope(lres, rres)
            
    
    def get(self, i): #a_iの値を返す
        return self.data[self.N0 + i]

n = int(input())
abc = [list(map(int, input().split())) for _ in range(n)]
abc.sort(key = lambda x:(-x[0], x[1]))
se = {0} | {b for _, b, _ in abc}
dic = {b:i for i, b in enumerate(se)}
l = len(se)
seg = SegTree(l, 0, max)
for _, b, c in abc:
    b = dic[b]
    tmp = seg.query(b + 1, l) + c
    if tmp > seg.get(b):
        seg.update(b, tmp)
print(seg.query(0, l))