There is a subtle difference between generating five random numbers and selecting the first five of a randomly ordered set. (The former allows the possibility of duplicates.) Your text implies the former while your code implies the latter. Here is code for the former.

use strict;
use warnings;
printf "%2d\n", 1 + int(rand 50) for (1..5);
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UPDATE: Changed 'code' to 'text' as pointed out by GrandFather.