How does calling srand more than once affect the quality of randomness?

Question

This comment, which states:

srand(time(0)); I would put this line as the first line in main() instead if calling it multiple times (

Answer 1

The seed determines what random numbers will be generated, in order, i.e. srand(1), will always generate the same number on the first call to rand(), the same on the second call to rand() and so on.

In other words, if you re-seeded with the same seed before each rand() invocation, you'd generate the same random number every single time.

So successive seeding with time(0), during a single second, will mean all your random numbers after re-seeding are actually the same number.