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How to Efficiently Generate Unique Random Numbers Within a Specific Range?
How to Efficiently Generate Unique Random Numbers Within a Specific Range?
Dec 05, 2024 am 04:55 AM
Generating Unique Random Numbers within a Range
Question: How can I efficiently generate unique random numbers within a specified range?
Answer:
The provided code generates random numbers within a range but may not guarantee uniqueness. For an optimized solution, consider the following approaches:
1. Array with Random Order:
- Generate an array of numbers within the range (range(min, max)).
- Shuffle the array using shuffle().
- This creates a random order of numbers, which can be sliced to the desired quantity for unique results.
2. Wrapped Function:
- Encapsulate the array shuffling technique in a function:
function UniqueRandomNumbersWithinRange($min, $max, $quantity) {
$numbers = range($min, $max);
shuffle($numbers);
return array_slice($numbers, 0, $quantity);
}
- Example usage:
print_r(UniqueRandomNumbersWithinRange(0, 25, 5));
Result:
An array of the specified quantity with unique random numbers within the given range.
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