php - how to select random index based on the current time -

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given array of length n, how select random index based on current time. wanted generate random integer 0 n based on current time. possible mathematically?

you can seed random number generator derived value time():

mt_srand(time() / 30 / 60); // reseed every 30 minutes  echo mt_rand(0, n);

without random number generator can use modulo:

echo (time() / 30 / 60) % n;

note mt_rand() output may include n whereas module version doesn't.


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