# LeetCode 18 – Letter Combinations of a Phone Number

#### Posted on December 25, 2013

##### Last updated on December 25, 2013

Solution to LeetCode Letter Combinations of a Phone Number problem.

This a simple recursion problem. To compute the translation of x:xs 1, we get all possible translation of xs, say t(xs), and take all the translations of x, $$t(x)$$, and compute the cartesian product $$t(x) \times t(xs)$$.

1. This is notation for an iterable element where x is the first element, and xs is the rest of the iterable

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