### 2.10.3 Product of disjoint cycles to permutation: `cycles2permu`

`cycles2permu` takes as argument a list of cycles.

`cycles2permu` returns the permutation (of size *n* choosen as small as
possible) that is the product of the given cycles
(it is the inverse of `permu2cycles`).

Input :

`cycles2permu([[1,3,5],[2,4]])`

Output :

`[0,3,4,5,2,1]`

Input :

`cycles2permu([[2,4]])`

Output :

`[0,1,4,3,2]`

Input :

`cycles2permu([[5],[2,4]])`

Output :

`[0,1,4,3,2,5]`