Project Euler Question 14 (Collatz Problem)

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The reason you’re stalling is because you pass through a number greater than 2^31-1 (aka INT_MAX); try using unsigned long long instead of int.

I recently blogged about this; note that in C the naive iterative method is more than fast enough. For dynamic languages you may need to optimize by memoizing in order to obey the one minute rule (but this is not the case here).

Oops I did it again (this time examining further possible optimizations using C++).

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