$ perl -le'
use List::Util q/shuffle/;

my $string_length = 600;
my $x_count       = 10;

my $joined_new_string = q/-/ x $string_length;

my @positions = ( shuffle 0 .. $string_length - 1 )[ 0 .. $x_count - 1
+ ];

substr $joined_new_string, $_, 1, q/X/ for @positions;

print $joined_new_string;
'
-----------------------------X----------------------------------------
+--------------------------------------------------------------------X
+---------------------------------------------------------------------
+----X----X-------X-------------------------------------X-------------
+---------------------------------------------X-X---------------------
+---------------------------------------------------------------------
+------------------------------------------------------------X--------
+---------------------------------------------------------------------
+------------------------X----------------------

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In reply to Re: Difficulty in randomization by jwkrahn
in thread Difficulty in randomization by Anonymous Monk

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