import sys

inputl = sys.stdin.read().strip().split("\n")
totaldistance = int(inputl.pop(0))

currenttime = 0
current_distance = 0

light_position = 0

for light in inputl:
    light_position, red, green = [int(x) for x in light.split()]

    currenttime += light_position - current_distance
    current_distance = light_position

    cycle_currenttime = red + green
    currenttime_relative_to_cycle = cycle_currenttime - \
        (currenttime % cycle_currenttime)
    if currenttime_relative_to_cycle - green > 0:
        currenttime += currenttime_relative_to_cycle - green
currenttime += totaldistance - light_position


print(currenttime)