import sys
from math import sqrt, pi, sin
inp = lambda : sys.stdin.readline()[:-1]
mii = lambda x = " ": [*map(int,inp().split(x))]
mfi = lambda x = " ": [*map(float,inp().split(x))]
ii = lambda : int(inp())
l = [0] * 1100
for i in range(ii()):
s, t, b = mii()
for i in range(s, t + 1):
l[i] += b
print(max(l))