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Old 02-22-2008, 03:22 AM   #1
Registered: Dec 2007
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Cool pseudo no generator srand generating similar nos every time

I have simply used srand and rand functions to generate random numbers but now i am finding every time even again compiling it is generating the similar set of numbers so what is the concept behind this ?
Old 02-22-2008, 04:56 AM   #2
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Rand() and srand() do not produce truly random numbers, as you have learned. The produce pseudo-random numbers. Rand() takes the value of srand() as the seed in producing a set of pseuro-random numbers. So long as the seed remains the same, so does the set of numbers returned by rand().

In order to produce different sets of numbers it is necessary to change the seed value of srand(). One common technique is to seed srand() with the current time (hour:minute:second). Each time srand() is called, when seeded with time, it will produce a different set of pseueo-random numbers.


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