N,L=map(int,input().split())

NOW=0
TIME=0

for i in range(N):
    x,w,t=map(int,input().split())

    TIME+=x-NOW

    if 0<=TIME%(t*2)<=t-w:
        NOW=x+w
        TIME+=w
    else:
        TIME+=t*2-TIME%(t*2)+w
        NOW=x+w

    
TIME+=L-NOW

print(TIME)