Why Does `rand()` Produce the Same Sequence Every Time, and How Can I Fix It?

Why Does rand() Return a Predictable Sequence?

The rand() function produces a seemingly random sequence of numbers. However, if you notice it generates the same values in every program run, this issue arises because the random number generator's seed is not initialized.

To remedy this problem, use srand((unsigned int)time(NULL)), which generates a seed using the current time, ensuring a true randomness factor in the sequence. This is particularly relevant for functions like rand() that utilize a pseudo-random number generator, where the generated numbers are not genuinely random but rather follow a deterministic pattern.

By initializing the seed with a truly random number, you can break the repetition and obtain a more unpredictable sequence. For further understanding, refer to the following resources:

• http://www.dreamincode.net/forums/topic/24225-random-number-generation-102/
• http://www.dreamincode.net/forums/topic/29294-making-pseudo-random-number-generators-more-random/

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