Why Does My C rand() Function Return the Same Random Number Multiple Times?

Function Outputs the Same Random Value Multiple Times

In C , the rand() function is frequently utilized to create random numbers. However, when this function is called multiple times within a single function, it may generate identical results. This can be perplexing, especially for novice programmers.

To comprehend this issue, it's crucial to grasp how rand() works. Internally, it maintains a seed value, which it uses to generate a sequence of numbers. By default, srand() is initialized using the current time, ensuring that the seed is unique across different function calls.

However, when srand() is called again, the seed is reset, causing the sequence of numbers to restart. This results in the same random numbers being generated each time rand() is invoked.

To resolve this issue, it's imperative to avoid calling srand() before each call to rand(). Instead, srand() should be initialized only once, typically at the beginning of the program, to ensure that the seed is set correctly and maintained throughout the program's execution.

By implementing these changes, you can ensure that rand() reliably generates unique random numbers, eliminating the issue of duplicate outputs.

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