Reservoir problem Extension: oil transport problem

Reference article: http://www.cnblogs.com/lulup/p/4133431.html

Question:The two places are 1000 kilometers apart, there are 3000 litres of oil at a, there is now a car from a to B to the oil, a maximum of 1000 liters of oil, the car every 1 kilometers to consume 1 liters of oil, ask how many liters of oil can be transported to B?

Solve:

This problem can be converted to 3000L oil can run up to how far:
Divide the whole journey into several segments, each with a few trips.
Every part of the journey should be transported all over the oil, and when the car is always full of oil, the return of the car is always empty.
To meet this requirement:
The first paragraph must return at least 5 times, forward 1000/5=200km, remaining 2000L oil
The second paragraph at least to a total of 3 times, forward 1000/3=333km, the remaining 1000L oil
The third paragraph opened directly to the end, opened (1000-533) KM, so there is still 533L of oil left.

Reservoir problem Extension: oil transport problem