n,l = map(int, raw_input().split())
ls = [map(int, raw_input().split()) for _ in range(n)]
time = 0
pos = 0
for [x,w,t] in ls:
    reach = time + (x-pos)
    cycle = reach / (2*t)
    if cycle * 2 * t <= x and x+w <= cycle * 2 * t + t:
        time = reach + w
    else:
        wait = (cycle+1)*2*t - reach
        time = reach + wait + w
    pos = x + w
time += l - pos
print time