WA in ATOM

i dont know why m getting wrong answer here…can any1 help…http://www.codechef.com/viewsolution/3316227

"Given initial atoms, limit on atoms and multiplication rate, find the time at which reaction has to be stopped.

Simple simulation: Most submissions to this problem failed because of overflow, and using log functions."

Here’s the official solution to this problem for you: http://www.codechef.com/viewplaintext/3389330
Your error? The overflow/usage of the log function.

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