6 different random unique numbers php [duplicate]

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• Generating UNIQUE Random Numbers within a range - PHP 10 answers

I have generated in an array 6 random numbers using the rand () function. I would like to ensure that none of these numbers are duplicates. I have written:

$lucky_numbers = array (rand (1,50), rand (1,50),rand (1,50),rand (1,50),rand (1,50),rand (1,50));
if ($lucky_numbers[0] == $lucky_numbers[1]) {
    print "same"; $lucky_numbers[1]++;
}
if ($lucky_numbers[1] > 50) {
    $lucky_numbers[1]= $lucky_numbers[1]- 6;
}

and then checked each consecutive number with a similar code. But something doesn´t work. Any ideas ? Thanks in advance.