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 ## Probability
   * [Addition Rule](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/probability/addition_rule.cpp)
+  * [Poisson Dist](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/probability/poisson_dist.cpp)
 
 ## Range Queries
   * [Bit](https://github.com/TheAlgorithms/C-Plus-Plus/blob/master/range_queries/bit.cpp)