The Incas used a sophisticated system of record keeping consisting of bundles of knotted cords.
Such a bundle of cords is called a quipu. Each individual cord represents a single number.
Surprisingly, the Incas used a base-10 positional system, just like we do today. Each digit of a number
is represented by a cluster of adjacent knots, with spaces between neighboring clusters. The digit is
determined by the number of knots in the cluster.
For example, the number 243 would be represented by a cord with knots tied in the following pattern
-XX-XXXX-XXX-
where each uppercase 'X' represents a knot and each '-' represents an unknotted segment of cord (all quotes for clarity only).
Unlike many ancient civilizations, the Incas were aware of the concept of zero, and used it in their quipus.
A zero is represented by a cluster containing no knots.
For example, the number 204003 would be represented by a cord with knots tied in the following pattern
-XX--XXXX---XXX-
^^ ^^^
^^ ^^^
^^ two zeros between these three segments
^^
one zero between these two segments
Notice how adjacent dashes signal the presence of a zero.
Your task is to translate a single quipu cord into an integer. The cord will be given as a String knots
containing only the characters 'X' and '-'. There will be a single '-' between each cluster
of 'X's, as well as a leading '-' and a trailing '-'. The first cluster will not be empty.
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