Unique random number sequence using qrand () and qsrand ()

Question

I want to generate a unique sequence of random numbers in QT using QDateTime :: currentDateTime (). toTime_t () as a starting value, qrand () generates unique random numbers?

Answer 1

No. qrandcan only generate as many unique numbers as fit into an integer, so - regardless of implementation - you cannot count on uniqueness.

Also, knowing that another seed creates another random integer will give you a level of predictability that actually makes it qrandno longer random.

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Answer 2

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Answer 3

Qt Documentation, QRand - rand(), , / rand() .

I think you need to use a different terminology than "unique" random numbers (no pseudo random number generator will create a unique stream, since input X will always produce output Y). What is the real situation?