Improve search by ID performace

[anshumanv]

We are iterating over each object to match it's num, this is poor in terms if performance, please improve it.

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What is a different way it could be done?

[Monal5031]

Well we can map the values to object and then do a BST over the numbers and retrieve back the chain we need.

[dericcain]

I gave this a shot in #46. This was a really good case for using a lookup table.