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diff --git a/challenge-135/adam-russell/blog.txt b/challenge-135/adam-russell/blog.txt
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index 0000000000..9f6c523296
--- /dev/null
+++ b/challenge-135/adam-russell/blog.txt
@@ -0,0 +1 @@
+http://www.rabbitfarm.com/cgi-bin/blosxom/2021/10/24/perl
diff --git a/challenge-135/adam-russell/blog1.txt b/challenge-135/adam-russell/blog1.txt
new file mode 100644
index 0000000000..ab4d53b90b
--- /dev/null
+++ b/challenge-135/adam-russell/blog1.txt
@@ -0,0 +1 @@
+http://www.rabbitfarm.com/cgi-bin/blosxom/2021/10/24/prolog
diff --git a/challenge-135/adam-russell/perl/ch-1.pl b/challenge-135/adam-russell/perl/ch-1.pl
new file mode 100644
index 0000000000..c4778b44a2
--- /dev/null
+++ b/challenge-135/adam-russell/perl/ch-1.pl
@@ -0,0 +1,24 @@
+use strict;
+use warnings;
+##
+# You are given an integer.
+# Write a script find out the middle 3-digits of the given 
+# integer, if possible, otherwise throw sensible error.
+##
+use POSIX;
+sub middle_3{
+    my($i) = @_;
+    $i = abs($i);
+    my $length = length($i);
+    return "even number of digits" if $length % 2 == 0;
+    return "too short" if $length < 3;
+    my $middle = ceil($length / 2);
+    return substr($i, $middle - 2, 3);
+}
+
+MAIN:{
+    print middle_3(1234567) . "\n";
+    print middle_3(-123) . "\n";
+    print middle_3(1) . "\n";
+    print middle_3(10) . "\n";
+}
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diff --git a/challenge-135/adam-russell/perl/ch-2.pl b/challenge-135/adam-russell/perl/ch-2.pl
new file mode 100644
index 0000000000..9d4e5c2161
--- /dev/null
+++ b/challenge-135/adam-russell/perl/ch-2.pl
@@ -0,0 +1,55 @@
+use strict;
+use warnings;
+##
+# You are given 7-characters alphanumeric SEDOL.
+# Write a script to validate the given SEDOL. 
+# Print 1 if it is a valid SEDOL otherwise 0.
+##
+use boolean;
+
+sub is_sedol{
+    my($sedol) = @_;
+    my $base = substr($sedol, 0, 6);
+    my $check_digit = substr($sedol, 6, 1); 
+    ##
+    # check length
+    ##
+    return false if length($sedol) != 7;
+    ##
+    # check for alphanumerics only
+    ##
+    my $test_base = $base;
+    $test_base =~ tr/[0-9][B-Z]//d;
+    return false if $test_base;
+    ##
+    # confirm the check_digit
+    ##
+    return false if $check_digit != compute_check_digit($base);
+    ##
+    # all tests passed!
+    ##
+    return true;
+}
+
+sub compute_check_digit{
+    my($base) = @_;
+    my @chars = split(//, $base);
+    my @weights = (1, 3, 1, 7, 3, 9),
+    my $sum = 0;
+    do{
+        my $c = ord(shift @chars);
+        if($c >= 66 && $c <= 90){
+            $sum += (($c - 64 + 9) * shift @weights);
+        }
+        if($c >= 48 && $c <= 57){
+            $sum += (($c - 48) * shift @weights);
+        }
+    }while(@chars);
+    return (10 - ($sum % 10)) % 10
+}
+
+MAIN:{
+    print is_sedol(2936921) . "\n";
+    print is_sedol(1234567) . "\n";
+    print is_sedol("B0YBKL9") . "\n";
+}
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diff --git a/challenge-135/adam-russell/prolog/ch-1.p b/challenge-135/adam-russell/prolog/ch-1.p
new file mode 100644
index 0000000000..47dea728e3
--- /dev/null
+++ b/challenge-135/adam-russell/prolog/ch-1.p
@@ -0,0 +1,25 @@
+:-initialization(main).
+
+middle_three(N, Middle3):-
+    number_chars(N, Chars),
+    N > 0,
+    length(Chars, Length),  
+    Length > 2,
+    IsOdd is Length mod 2, IsOdd == 1,
+    length(M3, 3),
+    PrefixLength is ceiling(Length / 2) - 2,
+    length(Prefix, PrefixLength),
+    append(Prefix, Middle, Chars),
+    append(M3, _, Middle),
+    number_chars(Middle3, M3). 
+
+middle_three(N, Middle3):-
+    (N < 0, N0 is abs(N), middle_three(N0, Middle3));
+    (number_chars(N, Chars), length(Chars, Length), Length < 3, format("too short~n", _));  
+    (number_chars(N, Chars), length(Chars, Length), IsOdd is Length mod 2, IsOdd == 0, format("even number of digits~n", _));
+    middle_three(N, Middle3). 
+    
+main:-
+    middle_three(1234567, Middle3),
+    ((nonvar(Middle3), format("~d~n", [Middle3]), halt);
+    halt).
\ No newline at end of file
diff --git a/challenge-135/adam-russell/prolog/ch-2.p b/challenge-135/adam-russell/prolog/ch-2.p
new file mode 100644
index 0000000000..c5361fc78f
--- /dev/null
+++ b/challenge-135/adam-russell/prolog/ch-2.p
@@ -0,0 +1,73 @@
+:-initialization(main).
+
+weight(1, 1).
+weight(2, 3).
+weight(3, 1).
+weight(4, 7).
+weight(5, 3).
+weight(6, 9).
+
+base --> alphanumeric, alphanumeric, alphanumeric, alphanumeric, alphanumeric, alphanumeric.
+alphanumeric --> [AlphaNumeric], {letter_or_digit(AlphaNumeric)}.
+
+sedol(Sedol):-
+    var(Sedol),
+    sedol(_, Sedol).
+sedol(Sedol):-
+    nonvar(Sedol),
+    length(Base, 6),
+    append(Base, [CheckDigit], Sedol),
+    phrase(base, Base),
+    compute_check(Base, ComputedCheckDigit),
+    CheckDigit == ComputedCheckDigit.
+    
+sedol(Base, Sedol):-
+    phrase(base, Base),
+    check_digit(Base, Sedol).
+
+letter_or_digit(A):-
+    nonvar(A),
+    atom_codes(A, C),
+    ((C >= 66, C =< 90);
+     (C >= 48, C =< 57)).
+
+letter_or_digit(A):-
+    var(A),
+    ((between(66, 90, C));  %B through Z
+     (between(48, 57, C))), %0-9
+    atom_codes(A, [C]).
+
+compute_check(Base, CheckSum):-
+    compute_check(Base, 1, CheckSum, 0).
+compute_check([], _, CheckSum, PartialCheckSum):-
+    CheckSum is mod(10 - mod(PartialCheckSum, 10), 10).    
+compute_check([H|T], Index, CheckSum, PartialCheckSum):-
+    atom_codes(H, [C]),
+    between(66, 90, C),
+    weight(Index, Weight),
+    LetterValue is C - 64 + 9,
+    Partial is PartialCheckSum + (LetterValue * Weight),
+    succ(Index, I),
+    compute_check(T, I, CheckSum, Partial).
+compute_check([H|T], Index, CheckSum, PartialCheckSum):-
+    atom_codes(H, [C]),
+    between(48, 57, C),
+    weight(Index, Weight),
+    NumeralValue is C - 48,
+    Partial is PartialCheckSum + (NumeralValue * Weight),
+    succ(Index, I),
+    compute_check(T, I, CheckSum, Partial).
+    
+check_digit(Base, BaseCheckDigit):-
+    compute_check(Base, CheckDigit),
+    append(Base, [CheckDigit], BaseCheckDigit).       
+
+
+main:-
+    (sedol(['2','9','3','6','9','2',1]), format("1~n", _);
+     format("0~n", _)),
+    (sedol(['1','2','3','4','5','6',7]), format("1~n", _);
+     format("0~n", _)),
+    (sedol(['B','0','Y','B','K','L',9]), format("1~n", _);
+     format("0~n", _)),
+    halt.
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