Proficiency needed in terms of Codechef rating to get into companies like Google?

What would be the approximate skill level in terms of rating needed to clear Algorithm rounds at companies like Google/MS/Amazon? (Assuming rating indicates skill level)

@simha

You can instead buy the book cracking the coding interview. This is the best selling book for gettin into the top notch tech companies like those you mentioned. You can read about this book on quora.

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