Challenge: Car Fueling

Problem

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Car Fueling Problem

Compute the minimum number of gas tank refills to get from one city to another.

Input: Integers $d$ and $m$, as well as a sequence of integers: $stop_{1} < stop_{2} < \ldots < stop_{n}$ .
Output: The minimum number of refills to get from one city to another if a car can travel at most $m$ miles on a full tank. The distance between the cities is $d$ miles, and there are gas stations at distances $stop_{1}, stop_{2},\ldots, stop_{n}$ along the way. We assume that a car starts with a full tank.