#coding: utf-8
#yuki_139

n,l=map(int,raw_input().split())

now=0
time=0
for i in xrange(n):
 x,w,t=map(int,raw_input().split())
 time+=x-now
 now=x
 next=(time/(2*t))*2*t
 if next+t<time+w:
  time=next+2*t
time+=l-now
print time