Kata

Imagine XO game like this :

   1 | 2 | 3
   4 | 5 | 6
   7 | 8 | 9
   
XO_Map = "123456789"

Write a function that receives XO_Map returns the winner.

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Example #1:

XO_Winner("OXX4O6X8O")

This should return "O"

The map :

   O | X | X
   4 | O | 6
   X | 8 | O

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Example #2:

XO_Winner("OXXXXOOOX")

If there's no winner return ""

The map :

   O | X | X
   X | X | O
   O | O | X

Enjoy !!!!!!!!!!!!!!