n, l = map(int, input().split())
T = 0
bef = 0
for _ in range(n):
    x, w, t = map(int, input().split())
    T += x - bef
    tmp = T % (2 * t)
    if tmp + w <= t:
        T += w
    else:
        T += 2 * t - tmp + w
    bef = x + w
print(T + l - bef)